I've gotten poor treatment after giving 10% on a $18 drink before.
Edit: so I guess I'd ask what is the approximate reference price for your "A dollar" comment? Cause if it's a $5 can of beer, vs a $20 cocktail those are very different tips.
$18 cocktails are pretty expensive. I work at a brewery so I’m not used to that.
I have always understood the rule of thumb to be $1 for “poured” drinks (beer, wine, etc) and $2 for cocktails.