I have to ask, are you really serious with this thought or are you just being tongue in cheek?
I'm willing to concede that at Princeton, the population may not be all hard-working, intelligent students. If Admissions does their job properly, though, it should be.
My high school was extremely competitive. Teachers graded f, d-,d,c-,c,b-,b,90,91,92,93, etc.to 100.
There were classes that ran from b to 98 or higher. Why not?
If the school is too tight on grades, then potential grad school applicants will have to flood the easy courses or be out-competed not only by their classmates by by foreign gad school applicants.