Well, let's say the average drink price you paid was $7. The total bar bill would be $56 (assuming you had eight drinks total and not eight drinks apiece!). Fifteen percent of $56 is $8.40, while a buck a drink is $8. Not much difference there.
However, tipping is highly personal, based on any number of variables. The main question is: How was the service?
Did the cocktail waitress ignore all her other customers in order to treat you like royalty, pay for a few rounds herself, then go home with one of you? The sky's the limit.
Was she friendly, attentive, and prompt? Did she get all your orders right? Did she clear off the empty glasses and replenish your napkins? Twenty percent of the bar tab would be generous, especially for inflated drink prices; at $7 a drink, that's an $11 tip.
Was she polite and professional, providing decent drink service but nothing special? A $5 bill might be about right.
Was she slow and surly or did she seem put-out? Leave her a buck.
Did she spill a tray of drinks on your wife's lap, not apologize, and charge you for the round anyway? Stiff her.
Could she not get anything right, despite trying real hard? Did she then claim it was her first night, the bartender was impatient, and her new high heels were killing her? We'd probably leave her a 50-cent-a-drink sympathy toke for effort and sincerity (even if she was lying through her teeth).
Did you just hit Megabucks and not notice the service at all, good or bad? A nice Benjamin would spread the wealth, make you feel good, and account for one of the 100,000 Benjamins in your pocket (at the Megabucks reset of $10 million).
As you can see, it all depends on the server, your mood, your money, and circumstances. But generally speaking, for two rounds of eight drinks at $50-$60, $5-$10 covers most of the variables.
