1) It's a private business -- Murphy's rules, baby.
2) Murphy knows he needs to find & retain good staff in order to keep his customers
3) If the staff hate the FSPers because they don't tip, eventually one or the other has gotta go
4) 80+% of the FSPers tip like 80+% of normal people
5) ~20 of the FSPers tip extra cause we are like that (d_goddard proudly tips at LEAST 20% for decent service, especially on a damn $10 order)
6) <1% of FSPers don't tip either due to some weird moral theory (Barskey) or because they are cheap bastards (no names given)
7) Murphy's calculation to lose one guy who buys less than $20/week vs. pissing off a hard-o-find good server was an easy one
If you think tipping is stupid, OPEN UP YOUR OWN DAMN BAR and implement a no-tips policy. Have fun finding waitstaff!