UK is an NBA player factory. High school superstars go in and professional players emerge a year or so later. North Carolina is not about that. High school superstars go in and they remain homeboys through graduation and beyond. Since I abjure professional sports, I'll be rooting for the Tarheels.
North Carolina is one of the top five states for Division I basketball recruitment, three others of which are concentrated around North Carolina. This gives UNC an ample recruitment pool (though crosstown rival Duke, gets some of the best). Kentucky would be hard pressed to recruit on equal grounds with North Carolina, so they resort to luring kids with the prospect of making big bucks as a pro.
UNC recruiters might explain to their prospects that they are among the 5% of high school hoopsters that will have a chance to play on a Division I team. After that, the chances of making it straight to the NBA is even less (3.6%, or about one player out of 28). UNC and UK (especially) recruit some of the more promising pro prospects, so their chances are actually higher. However, UK players are more likely to be disappointed, since that's what their program is mainly about and a good many of them never get drafted.
Kids should play just for the thrill of victory. Then their spectacular feats can be the talk of the town, but that's about it. Well ok. An Olympics every four years is fine, but only if we can completely drop the egomania of pro sports. Maybe then, the Olympics would no longer tip host countries into financial ruin.