The most prestigious schools in the most difficult degrees might be difficult if you are a crappy student. That's probably for the best. If the US can you study in one of those "tuition mill" schools and become a doctor or an aviation engineer and work in your field?
Yes, although there are some limitations there: medicine has a high barrier to entry and engineering requires an accredited degree and certification. Most of the tuition mill students get "information technology" or similar degrees that lack strong professional organizations.
That would be the other side of the coin: if you do poorly on the exam or have poor grades, your choices are limited, no?
The upside of the American system is that anyone can get higher education. The downside is that many of the schools are tuition mills.