In many/most states, the minimum wage for a variety of jobs is not in the range of "livable". For example, minimum wage for restaurant jobs in Georgia is $2.13/hour [1]. They actually don't "get paid enough for this shit," so their attitude actually matches reality. Tipping is a necessary component of the compensation if we want to continue our practice of letting certain employers have exemptions from labor laws.
EDIT: $2.13/hour is $340.80 per month, if you are given enough hours to make full-time. Taxes etc. come out of that (you will probably see some of that money again when you file your taxes, for all the good it will do then).
(Yes, I know the employer is supposed to top-up the staff to e.g. $7.25/hr. That does not always/usually/ever happen.)
You are correct that paying people more than a pittance changes how they view their jobs.