Nope, never. I once had the unfortunate experience when i was younger of gas spraying back on me from topping off too much so I’ve learned my lesson. I just stop when it clicks the first time.
Please explain how fuel is wasted. 
It would never have occured to me to do this, and I can’t think of a single reason, other than whimsy, to do so. The only time I wouldn’t just fill up my tank is if I expect the price to go down significantly in the near future.
Yep, me, too - same line of thinking. And not just rounding it off, I like it to be an even number.
$40.00, $38.00. I hate when it rounds out to an odd amount.
I do it with my personal vehicle and my work vehicle.
I think the reason I do this (make sure it ends on a .00 amount) is because I expense my gas for work, so, in my mind anyway, I want to get back a nice round amount when my expense check comes rolling in. (It very rarely works out this way due to other things that end up on my expense report.)
Plus, if I didn’t do it this way, the world would cease to exist.
99% of my gas purchases are at place I am a repeat customer. I do a different thing at each.
I can instantly see if I was the card user and if not, at which place the crook used the card.
ID theft and CC ripoffs are a real PITA, ask those who have suffered.
We have so little $$$, we have to be ANAL about it.
Nope.
I specifically pump an uneven dollar amount. Fifteen years ago, before pay-at-the-pump was prevalent, I frequented an Amoco station and paid inside. Someone there sent through a bogus transaction for an even $20. When I reviewed the monthly statement, that number stuck out like a sore thumb. Even though I rarely pay at the cashier anymore, I still pump an uneven amount.
No. I pump until the handle clicks and that’s it.
Nope. When it clicks, that’s sufficient.
Its OCD, but its harmless in this form. No one gets hurt; no money is wasted, etc.
Its just a way that your mind has found to get rid of stress.
I did not know that. I almost always go for the second or even third cut-off. Not to round off the figure, but just to fit more petrol in because I know it will have gone up by another 2p a litre next time I fill up 
I almost never do. When it clicks off, that’s it. The only time I aim for a certain amount is when I am filling a gas can for the mower.
I just filled up my van. Just pump 'til the pump clicks off and that’s it.
I’m of the “pump till it clicks” persuasion.
GT