Do yourself and restaurant employees a favor, then, and don't. Don't order delivery food, either.
Waiting tables is a nasty, stressful and thankless job. If you've ever worked at restaurant, you'd know this. Of course, if you'd ever worked in a restaurant, you wouldn't call their employees whiners.
Scouts Out! Cavalry Ho!
Why? When we go out we do tip well when it is merited. But I do not appreciate someone attempting to "shame" me for leaving a justifiably bad tip. If the service sucks, you will get a lousy tip, I promise. But if the service is great, I will tip generously (over 20%). As we have young children with us when we dine, I find myself routinely giving out 25% (or whatever the next higher dollar is) in tips because the waitstaff does a lot of cleaning up during and after our meal.
Waiting tables is a nasty, stressful and thankless job.
Again, if someone don't like the job, then he can get another one that isn't so nasty, stressful or thankless. In the mean time, he should do the job he signed up to do. Everyone gripes about work, so I don't see why people in this job who gripe are any different than those in other lines of work who gripe.
Of course, if you'd ever worked in a restaurant, you wouldn't call their employees whiners.
Even the ones who whine?