>Why do you have a major problem with consenting adults at college level, but not at professional level? How is consenting-for-money any different to consenting-in-hopes-of-money?

Because often the offers are made and accepted when the person is underage and the collusion to keep there being no pay. If colleges didn't get involved at all until people were 18 and players were paid I wouldn't have an issue.

It is like the difference between a college student who meets and dates an older individual vs a college student who dates someone who knew and groomed them while they were still a child. Both may be legal, but far more people will be appalled at the second one.