Why practice when you could get hurt?
You can't get better if you don't practice. All players do it. Remember when just about the entire C's team when out to LA for a week and played over the summer.
Jordan had guys come out during his Space Jam shoot and played pick up games.
People worry too much about injuries. If it's going to happen it's going to happen. Guy's could roll and ankle walking on the side walk. Tear an ACL just jogging or going up the stairs. They could get hurt first day of training camp, what are they not suppose to do that too?
It's not like he's wrestling, or ufc fighting, or running from the bulls, he's doing what he's suppose to be doing.