Does one pay first and then get a plate or is one expected to pay at the end of the line?
The salad bar and the front counters in most stores are right next to each other, and you pay first then get your plate.
Last Saturday we had some people come up to the salad bar just using the plates we give out to serve the pizza on, we didn't demand to see if they paid for their salads, we just handed them regular plates, truely the few cents we lose on the salad bar is better than a confrontation like happened in this case.