Couple of things, why would anyone think it was worth it to them for the players to have to come up with less money or for the season to be shut down?
Are ticket prices suddenly going to plummet? Are concessions and parking suddenly going to have price cuts? Are you now going to be able to afford a real Pierce and Rondo NBA Properties Official jersey without having to take out a second mortgage on your house?
Second, remember that a 50/50 split on BRI doesn't mean the players are getting 50% of all NBA generated revenue. the owners get to not share 60% of proceeds from arena signage,
60% of proceeds from luxury suites, 50-55% of proceeds from arena naming rights, and all expansion fees incurred. I don't know what the exact breakup is but I have seen estimates that this can total, depending on year, anywhere from 2-5% of total revenue generated by the NBA.
And none of this includes other business ventures that owners might be making outside of the NBA that is tied into the NBA like local restaurants, hotels, bars, novelty stores not directly related to the team and a host of other things.