By the way, it’s illegal in the US for the restaurant to deduct any shortages from the waitress.
https://www.dol.gov/agencies/whd/fact-sheets/15-flsa-tipped-employees
I think you either trust your employees not to steal or you fire them, but it seems messed up to say “Sometimes people are going to stiff the bill, this is not your fault and there’s nothing you can do about it, but we’re going to punish you for it regardless because you might be a thief.” Just doesn’t feel right. (And apparently is also illegal). It wouldn’t fly in any other environment either, like if a printer went missing from my office and my key fob indicates that I was the last person there, but I say it was the cleaning crew, my company can either believe me or they can fire me, but they can’t say, “We believe that it was the cleaning crew but we’re docking your pay because if not other people will feel like there’s nothing stopping them from stealing printers and blaming the cleaning crew.”
They should just assume I did not stiff them and not follow me out, IMO.
There’s a possible semantic issue in this type of thing. If you mean ‘I don’t know why I, ‘Joey P’, wouldn’t go back to that place’ that’s completely fine. But I ‘Corry El’ will choose from among generally numerous* eateries on the slightest reason that makes sense to me. As long as I’m there I believe I’m more understanding than most people of any problems or issues that arise. And I wouldn’t be literally pissed off by being followed out and asked if I paid. But as to going back, no.
*pretty much innumerable where I live, literally dozens within easy walking distance, but in general there’s multiple choice on eateries most places. Recently I stayed in a town in NV with one restaurant and ~1 hr drive to any other town: fortunately it was good. 
You attached my name to the wrong post.
Oh, I don’t know about that. It’s fair of them to at least ask. But once I explained my side of it, if they choose not to believe me, well, fifteen dollars isn’t enough for me to fight them about it but the accusation (if not withdrawn) would be enough to make me stay away.
As for obligations, I certainly wouldn’t feel it my responsibility to pay the bill a second time just because somebody’s stealing from the restaurant’s tables. It probably wouldn’t even cross my mind to pay the tip a second time - I sort of mentally lump the tip in as just part of the cost of eating out, which it so say the bill (which in my mind was already paid).
This is why I insist on at least seeing the server pick up the money before I leave the restaurant.
Bob ---- but society is to blame.
I just had to add the Python reference.
Right or wrong, we’ve got to know, what’s Bob’s race/ethnicity?
And this kind of reminds me of the old joke: two men, Andy and Bob, are robbed in a back alley. “Give me all your money,” says the assailant. Both Andy and Bob take their money out of their wallets, when suddenly Andy says, “Bob, here’s that $100 I owe you,” and gives it to him.
Is that debt actually settled?
Bob’s on the hook for it. The waitress will be able to establish that it looks like a classic “dine & dash”.
I think that Bob is responsible for seeing that the waitress or the cashier gets his money. But I’ve been in restaurants when it seemed that the waitress/waiter disappears after dropping off the check and have had to wait what seems like a good long time for them to return. So I can understand the desire just to leave money and walk out.
Bob did not remit or even proffer payment. He received a bill, assigned a specified sum to cover it… and then failed to give it to the restaurant or even attempt to give it.
That was his failure and that is why, in a situation where the thief remains hidden within in his Schrodinger’s box, Bob owes the restaurant its bill AND the waitress her tip.
The joke is funny, but the answer to your question is… Uh, No.
I think this argument is missing an important point. There may be restaurants where you can leave money on the table and that’s an accepted practice. But the OP specifically said that the waitress told Bob “I’ll be right back” when she gave him the bill. That indicates that she expected to receive the money directly from Bob. I feel this overrides any claim by Bob that he has left money on the table at other restaurants.
If I go to a buffet, I don’t sit down at a table and expect a waiter to bring me my food just because that’s the way they do it at other restaurants. I adapt my usual practice to the way they do it in this particular restaurant.
I wouldn’t go that far. I feel Bob attempted to pay the restaurant. But I feel the money was stolen before the transaction was completed.
He didn’t remit payment. He had to perform an action and he failed.
I have been Bob myself, leaving money on the table. But that passive action leaves me open to the liability, not the restaurant. They gave me the service I ordered. I still owe them the $. If I wanted to be totally absolved of that responsibility, I needed to make direct payment to the restaurant, not indirectly by leaving cash where the waitress… or anyone else… could grab it.
Bob. That’s the risk you take when you do something like that.
It was very much a “fuck you, pay me” type of relationship between waitstaff and management.
That’s what Bob gets for paying in cash.
A month or so ago I was in a dive bar sitting near a man and woman (husband/wife) who were very drunk. Every round of drinks, she paid, then took a dollar or two from her change and added it to a pile of bills on the bar that was going to be her tip at the end of the night.
She was barely able to stand. She decided enough was enough, put on her coat (with cringeworthy difficulty), and walked out the door. He stayed and ordered another drink. He also picked up his wife’s tip pile and counted it. He used the money to pay for his drink, put a dollar on the bar and the rest in his pocket, chugged his drink and left.
I told the bartender what I’d observed. She told me they do that all the time and she’s pretty sure that the wife knows what he does. She also told me they live a two minute walk from the bar.