Smart is right. Fans in Boston got banned for life for stuff like that, yet no action at all, not even a warning, was taken for this incident in Denver. If security doesn't protect players, players will protect themselves. Just because you bought seats to a game doesn't give you the right to verbally abuse the players with racist laden comments.
Tell the players they suck, can't shoot, are losers, whatever, but don't cross the line into personal and racist stuff.
I'm glad Smart retained himself and handled it well by informing security and then telling the media afterwards. A younger Smart would have decked the guy and been suspended for the season.