Exactly this. It's the easiest way to evaluate students while ensuring taht everyone has a fair chance. It sucks, but it's true.
However, what Andy_H said certainly is not true. This test is important, but it's not everything. Sure, everyone has their fair shot at the SAT, but some people are better test-takers than others. Plus, intelligence does not define work ethic. That's why colleges use the SAT as one of MANY tools for deciding upon who they accept. Just because you didn't score a 45893958 on the SAT doesn't mean you can't get into a great school.