There is a direct correlation (an inversely proportional one) of tips to shrimp taken home on Endless Shrimp orders. The more you put in the box, the less you leave on the table for a tip.
If you are eating Endless Shrimp, you should tip at least $3 per person for each meal ordered, plus whatever is appropriate for anyone/anything beyond that. I'm not asking for much, not asking that you leave $10 on a $16 check. But $3 per Endless Shrimp makes it worth it for your server.
Also, the more dressing you use, the lower on average my tip will be, with the exception of light dressings.
If you put butter on your biscuits, my tip drops. And by the way - holy fucking gawd - those biscuits are bathed in butter already. I don't think you could get more calories in them if you deep fried them. Enjoy your angioplasty. Same goes for dipping the biscuits in any form of dressing.
If you add the letter "K" to the word shrimp my tip goes down.
If it is 10PM and you roll in with your 3 year old and let them order Coke, my tip goes down.
The words Hennessy, Patron and Courvoisier all make my tip go down.
Any Scotch that isn't rail makes my tip go up.
Red wine improves my tip.
If you ask for your fried seafoods to be well done, my tip will suck.
If you ask for your steak to be well done, tip sucks.
If you use honey mustard on something other than your salad my tip goes up.
If you smell of weed my tip goes down. If you wear something with the image of weed on it my tip goes down further.
If you wear something that says Insane Clown Posse (ICP) my tip will suck.
If you wear a baseball hat during the meal my tip goes down.
If you wear a leather vest my tip goes up. Goes up further if you have a beard.
Cowboy boots + non-cowboy jeans usually means a good tip. Cowboy boots + cowboy jeans usually means a crap tip. But only on men.
If you are a dude and you walk in holding hands with another dude, my tip goes up. Confident gays tip well on average.
If you snap your fingers to get my attention, my tip goes down.
If you yell to me when I'm at another table, my tip goes down.
If you let your children run free through the restaurant like it is McDonald's fucking playland my tip goes down.
If your table has someone who is disabled - especially wheelchair bound - my tip goes up.
If you order the New England Sampler my tip goes up.
If you order fresh fish in any prep other than fried my tip goes up.
If you order the Rock Lobster tail (and the cooks don't fuck it up & make it rubber) my tip goes up.
If you ask for malt vinegar my tip goes up.
If you order the Steak Lobster and Shrimp Oscar my tip will be fat.