What was wrong with what the Ohio State players did?

It could be used as a way to funnel illegal payments to players. Let's say NCAA rules permitted those players to sell that stuff and keep the money. So a player puts his championship ring up for sale, and some wealthy booster buys it for $10,000. Let's say an award for winning the conference championship sells for $5000, another award for beating your cross-state rival nets $1000. Pretty soon high school players all over the country know that if you go to OSU, winning a national championship is going to earn you 10 or 20 grand, and it's all legal. Who would go to Michigan then? Other schools boosters would have to step up to stay competitive, and pretty soon it just comes down to which school has the wealthiest boosters.