The answer to that is that the waiter most likely had six or eight other tables
No, he's a waiter, he should know that the main course is served after the starter, not together. The place wasn't, by the way, busy.
And after a few questionable comments
You're assuming a lot - the people on our table were more surprised than anything, especially as we'd only started eating the starter and there was no room on the table for the main course.
The thing that makes a difference in a pizza to me is the sauce as the rest of it is basically the same.
A really good pizza is really good. Pizza in New York (those squares) are excellent, however the best I've had anywhere is at a little independent place in Warsaw (ul. Kopinska in Ochota). The guy who runs it won a prize for the best pizza in Melbourne before he came back to Poland and set up there. It's exceptional. The name of the place is Cucciolina.
The worst one I've had, in Poland or anywhere else, is (apart from Da Grasso/Telepizza) one froma delivery firm called Pizza w Nocy. That was spectacularly bad.
@Cardno85, yes. I suspect it's partly because they found that they get good sales from having a very bland product slathered with sauce.