If I go to a restaurant and get great service and have a good time... I tip in excess of 20%
If I go to a restaurant and I plan on coming back often... (Wok n' Roll for the DC peeps) I tip in excess of 25% so I get my way the next time I come.
If I'll never go back there... about 15%.
If they the experience sucks... you're lucky to see 5%. My girlfriend always makes me tip even if it sucks, but if she wasn't around there would be some servers getting pennies.
Also, what's wrong with going to a restaurant in shorts/flip-flops/hat/t-shirt? If it's summer and not a fine dinning establishment, I don't see a problem here? 8/10 times I go out it's to drink and just nosh on all their appetizers (I like variety). Plus, if it's summer and a weekend, pish-au.
I totally agree about the rug-rats though. If you're dumb enough to have kids, go to kid friendly restaurants at kid friendly times. Otherwise, get a sitter. It's good for the economy. Otherwise, I will teach your children bad words!
Cheap wine is just kool-aid? At most restaurants I go to, the cheapest they have is about $45, and that's equivalent to a $15 bottle, or so. There are some good values at that price. We're not talking about Mad Dog 20/20 here. Depending on my mood and where I am, I will order better wine, especially if the lower-priced selection sucks... but again, I don't see an issue here. Now, pretending to be a connoisseur of cheap wine, that's just douche-y.