Asking student-athletes to "stay out of trouble" and asking them to adhere to a set of arbitrary standards which are completely at odds from the student body of which they are ostensibly members are two hugely separate things.
You really might as well advocate having the football team live off-campus and take correspondence courses. Heck, why even have them live in Knoxville? They could train in Morristown and drive in for the games.
Since when did requiring student-athletes to obey not only state law but campus policy somehow get morphed into a, "set of arbitrary standards"?! Your statement is itself, arbitrary.
So, you're saying that it's draconian for the university to hold the student-athlete to such a standard, while knowing that the illegal activity is rampant throughout the other members of the student body? Well, then, you seem to have a much more pervasive problem with your "student-body", than the rules imposed on the conduct and actions of the student/athletes.
No matter how many times the "two-wrongs-make-a-right" argument is raised, nor how badly you want it to be true - it's not. If a million people violate the law, the next person to do so is just as guilty of the offense as the first. Your argument predicates that the pervasiveness of the problem (which the law was intended to correct, by the way) suggests that the law should be ignored.
Using that logic:
1. Of 1,000 people who don't fully stop at stop signs, only about 3-5 are actually caught and cited. I guess we should take all of the stop signs down.
2. Think of the thousands of people who cheat on their taxes each year and only a fractional amount of them get audited, and subsequently, caught. I guess we should just admit that because so many others cheat on their taxes, its unreasonable to expect others not to do the same, and they shouldn't be punished.
Do you agree with those things, too, or do you only attempt to rationalize illegal activity when it comes to the consumption / use of alcohol by underage college students?
The fact remains:
Underage drinking is illegal, and if consumed on campus, against the Universities own internal policies.
As such, I believe that it is not only reasonable - but necessary - to expect a student-athlete to abstain from violating either of them, regardless as to whoever or how many others may choose to do so.
Just my opinion, and likely, many will agree with you and think it wrong.