Pro teams run tubulars, which are significantly lighter than clinchers and have other properties that are important to racers but more hassle than most amateur riders want to deal with. But on any given day and course you will see riders making different choices in wheels and other equipment. Some of it is based on who is sponsoring them, but a lot of it is based on the rider's preference for the course.

Edit:

I'll also add that "more aero" often has tradeoffs. I have Zipp 404's on my primary bike and Hed Belgiums on my backup. On days that I am anticipating strong crosswinds, I'll opt for the bike with Heds because the bike is much more stable under those conditions. Being able to easily hold my line is more important to me than the aero benefits. On days that are more conducive to the 404's I'll take that bike mainly because I like it a little more.