Popped in and out of the Harrah’s poker room several times last time I was in New Orleans. IIRC, I was up about $200 for the trip, but I don’t remember how that broke down.
But this obviously isn’t right; if it was, the casionos would be out of business. As someone else said, you remember the wins, not the losses, but the truth is that everybody (who isn’t cheating) loses more than they win. Shooting dice (craps) is my game of choice in part because it has the best odds in the casino (other than BJ, which I’m not skilled enough at to make the odds favor me), and the odds there still favor the House. (And the House wins regardless of whether you win or lose, because they don’t pay true odds on a win, they pay house odds – meaning, they shave off and keep a portion of what you would have won under true odds.) The Casinos WANT you to think that lots of people win, that most everybody wins – that’s why they all have big photos of all their big payouts – but the truth is, most everybody loses in the end.
There’s no guarantee you will EVER hit a big jackpot. For every person who is down and comes back to a big win, there’s thousands of people who were down and then just went further and further down until they either wised up and walked away or literally ran out of money. Don’t be fooled by what the casinos WANT you to think.
IMO, the only way to gamble smart on table games or slots – assuming you’re not wealthy with unlimited money to blow – is to budget the amount of money you will waste gambling before you even go in the casino – and 9 times out of 10, it will be completely wasted. Then you play with that money until it runs out (or makes you enough that you want to stop – woohoo!), but when you have lost it all, you STOP. No dipping into the meal money, no reconsidering because your luck is sure to change, just a full stop. You can stop sooner and keep your money, of course, if you think the table’s cold or you’re just not having fun, but that’s the point at which you HAVE to stop.
I usually budget $100 a day for gambling for a trip to a casino town. I consider that money spent before I even lay it down on the table; I’m spending it for the enntertainment, just like on a show ticket or a movie ticket. If you consider the money already[ spent, then you won’t fell bad when you lose it. If you are not comfortable just setting fire to the money – because, chances are, that’s what you’re doing – then you should definitely keep it in your pocket, budget lower, or don’t gamble at all.
Keep going based on whether you are having fun and you can afford it under your gambling budget. Don’t keep going on the hope your luck will change and you will hit a big payout, because you almost certainly won’t.
Winner. I was in New Mexico for a tournament, and that night we went to a casino. I didn’t have any cash on me, so my friend loaned me twenty bucks. The second slot I played, I won thirty bucks. I wanted to be able to go home and tell my wife I’d walked out a winner, so I said “that’s it, I’m done!” and stopped right there. I just followed my friends around after that while they played and they didn’t notice I’d quit. My friend that loaned me the money went in and out of the hole a couple of times, but by the end of the night he was up a couple of hundred bucks. I offered him his twenty back on the way out and he said to just keep it. 
Got back from the Hilton in Vegas, came close to breaking even, a net loss of maybe $100. Had a blast though, and when you consider I got near $100 in free chips you can see I played for quite some time.
Net winner. Weekend in Las Vegas with absolutely no gambling, staying at the Luxor.
Had spent my budget and was just killing time, walking through the casino to get outside, found a quarter beside a slot. Put it in and got an immediate jackpot.
Spent the rest of the time playing slots, ended up with about $35 American with no expenditure - not bad – but at one point I had maybe twice that. Ftt.
Several years ago on Mother’s Day. Boat in Elgin. We blew $85 in about 10 minutes. Got off the damn boat, went back to sister in law’s house, and drank until the rest of the family came home. 
I have never won a dime at a casino. Ever.
Now if you want to talk Horseracing…
Net loser.
Was in Vegas with some friends, they kept bugging me the whole trip. “C’mon, Sofa, you can’t come to Vegas and not gamble!” Geez. Finally I stuck a couple quarters in a slot machine, lost (duh), and turned to them. “See? I gambled. Can we go catch the show now?”
Cruise ship, May '07. I won about $300 playing roulette, starting with $20 and gradually building it up by mostly conservative bets, like a third of the board, or four or six numbers at a time with a hedge in another part of the board. IIRC I did win one single-number bet at 35:1, but my bet was only $5.
I’ve only played roulette twice in my life and been lucky both times, so I’m sure I’m due for a loss next time.
Last time was at the Stratosphere in Vegas. Played $1.00 slots with 3 dollars per spin. Won $800.00 in about 5 minutes. 4 hours later won $600.00 at the same machine. Next day i lost about 100 at BJ, decided to quit while ahead but dropped $21.00 in the same slot machine as I was checking out.
I started with $40. At the end of the first night, I was up $5. At the end of 2 days, I was down $20 I hadn’t planned to gamble. I’m an addict, I tells ya! 
Hotel Hispaniola, in Santo Domingo, last December. Lost RD$4000 in about 2 hours.
I spent 3 days at the Taj Mahal in AC last month.
I played a little here and there and ended up losing $20 to the slots.
But the entire trip was comped thanks to my gambling obsessed mother.
Two suites at the top of the Taj (swanky!!), food, booze, tickets to shows we didn’t use, and more, all comped.
I lived like a high roller in the fancy VIP clubs like the Maharajah (gorgeous views) and Bengal, ate shrimp and crab and lobster and ordered champagne, wine, fancy desserts and room service like they were going out of style.
So, all in all, $20 at the slots didn’t seem like much.
My mother, on the other hand, who knows. She’ll win big jackpots every month or so (last one was $9K, one before was around $15K and got her picture put up on a billboard somewhere in NJ), but she’s down there every other week or so and I don’t think she ever goes with less than $1K to play with. She enjoys it and does get a lot out of it, so I guess I’d call her a net winner, but there really is no way for me to know.
120€ down last Sunday.
I play 1/2NL almost every Sunday. Very early on in the game I had a marginal bad beat (AA vs KK) and started steaming. Still have a healthy bankroll though.
It was three or four years ago. I lost about $30.
My last time in a casino was in Macau. I’ve gambled in Las Vegas, and I’ve gambled in Macau. In Vegas, I’m a net winner, while in Macau I’m a net loser. All in all, I’ve broken even, losing the exact same amount in Macau that I’ve won in Vegas. Really.
Vegas is more fun. I was disappointed that the Lisboa Casino in Macau does not allow you to drink while gambling. There’s one bar, in a basement room. The room is full of slot machines, but – get this – you cannot take your drink over to the machines; you must drink at the bar. The dealers there are all very dour, too.
I take $50 for the slots, knowing it will all be gone by the end. Plus a few bucks for food.
I’ve only ever been to a casino once, and I’m not 21, so I had to hand a dollar to the boyfriend to gamble in the penny slots for me. He lost it, so I gave him another one, and ended up with five or six bucks.
Huh. Last time I was in a casino, I didn’t gamble at all. I guess that makes me a winner. 
But the last time I gambled in a casino, I won US$300 on quarter slots. On the first pull. I took my money and left immediately, figuring I’d just used up that day’s allotment of luck. That was over 20 years ago… I’ve never been tempted to try again.
If you break even, you’re already ahead of most people.
My mom and I both won $140.00 the other day at one of the many Indian casinos here in CA. That was on the high side for me and on the low side for her. She usually wins between $500 and $1000 per trip. I usually lose most of what I bring.
I’ve been in a casino three times, in the early 90s. All three visits were to attend tryouts for Jeopardy.
[ol]
[li]Went with 20 dollars for the quarter slots. Lost all quarters. Was “led astray” by my mother-in-law who wanted to try the dollar slots, so I fed another three dollars to the machines and lost.[/li][li]Went with 10 dollars. Hit the biggest jackpot on the machine - payout, 40 bucks. Got briefly excited, fed a few more quarters into the machine, lost them, decided I might as well quit while I was ahead. Net gain, 30ish dollars for that trip. [/li][li]Got 10 dollars in quarters. Wandered aimlessly around the casino. Remembered that I hadn’t particularly enjoyed playing the previous time even though I had won. Realized the place stank of cigarette smoke and desperation and was largely inhabited by lonely looking middle-aged people and that it was artificial and hideously depressing and and it was no fun and I didn’t like being there. Left with my untouched roll of quarters.[/li][/ol]
eta: These were all at a casino in Atlantic City - I forget the name but I think it was owned by Merv Griffin Enterprises (who owned the Jeopardy franchise back then also).