heh, that reminds me of an experience at the airport. A skycap took my bags and I was getting into my carry -on for my wallet and having some trouble. He said, "yes sir, I'll be taking care of your bags." I continued digging for my wallet and a couple seconds later he said something like, "yep, I'm the person who makes sure you're bags get to where they need to be."
Finally I got my wallet and tipped him, but then I thought, was he nudging me for a tip or threatening to misplace my bags if I didn't??
Probably. I've worked a couple service industry jobs prior to my nice cushy government job. I can understand why people would not tip at bad service, and whole heartedly so, but one of the jobs I've worked was delivering pizzas. There were several houses we would deliver to that never tipped. Unless they were squatters living in $500,000+ houses, they were by all means not poor. I know every time I drove out to one of those houses I felt like doing something damaging to their property or pizza.
Never did though. I was just angry. There's also people who don't believe in tipping waiters and waitresses. Most everybody knows that they make less than minimum wage and they depend on their tips. If they don't make at least the equivalent of minimum wage per hour per the pay period worked, there's a law that says that the employer has to suppliment their income (usually $2.15/hour or so) to bring their wage up to the minimum. A lot of employers have policies where the employee has to pay this money back on the next check where they make enough to cover the minimum.
There's still people out there that go out to restaurants and won't tip a dime because they believe that they shouldn't have to, no matter how good of a service is provided. Usually the wait staff remembers people like this that repeatedly visit and insure they never get good service.
I know there's always certain circumstances where a person/family can't really afford to eat out and maybe want to treat a family member to something special and it's really hard to judge, but you just know when you have people visit an average dining establishment like Applebee's or Ruby Tuesdays at least once a week and never tip that they're not one of those poor people and just excercising their right to be a real rectum.
I always tip though. Usually more than 20%. I know a lot of people at the places I go to. They treat me well and are very friendly. I even tip my bartender friends who let me mostly drink for free. They think I'm wierd because they'll just not charge me for a $10 tab and I'll still tip that much.