I do tip well having been in the industry a long time. Extra if you seem like a genuine person, bartender who will chat you up, server who isn't a robot and simply seems like they like what they do. I'll tip even more if I can see that you are extremely busy, even if that makes your service less than what it could be. I've been there.
If every time my server comes by and they have their hands full, or are stopping at other tables in the area too, I'll go up to 30% if they just get the order right and it comes out hot. It will make up for the guy that tips 10% because the server wasn't on top of their every little tiny unnecessary need, and complains because their food is taking too long despite it being dinner rush on a Saturday night.
Now if the place is slow, I never see you, I have to flag you down because your off chatting with co-workers, then it goes down because there is no excuse.
Bottom line in service, if you can't tip 20% for good service, go get fast food.
Delivery I do about 15%, couple bucks more if it is nasty weather like the chart says. Carry out 10% because you're not really like getting me drinks, checking on me, but you do have to box it all up which is more annoying than it sounds, having done it.
I'll give a few bucks to the baggage handlers at the airport now. Only the ones outside seem to take tips. I look at it as a few bucks so I don't have to stand in the long ass line inside because the outside guys hustle and get people on their way. And if you don't tip them, maybe your bags end up in Seattle when you were going to Miami. Maybe your bags get handled with less care than normal. Maybe not though, don't want to find out.