Because it’s mostly white dudes doing it? 
You are 100% right, I have no patience for that crap either.
Yeah, possibly. Or it may even be simpler:
“Go team!” is way less difficult to process than “there are systemic problems with law enforcement in the United States”. Folks at a game don’t want their attention brought to difficult social problems - they want to be diverted and entertained.
I’m absolutely not saying that is a valid or correct, but I do think is a pretty plausible explanation.
Which is why Cuban’s decision is exactly correct. If fans don’t want politics in their sports then they shouldn’t play the anthem at all.
NBA is 74% black and I cannot recall any players backing Trump , at least in public.
NHL Dallas stars are still using the anthem
I follow the Premier League and they don’t play God Save the Queen before games. I don’t remember hearing anthems at other European major league games either.
At least the NHL (any team in any city) has the excuse that they often host foreign teams where custom demands both anthems be played. NBA? Not so much.
Although anthems at bi-national games is also a custom that pro sports leagues probably ought to drop. Events like the Olympics where the team genuinely represents their entire country are a plausible reason to play national anthems. Anywhere else it’s just advertising for jingoism.
Better for each team in a league to develop a theme song / fight song and play both of those before a pro game of {whatever}.
Now the NBA is requiring that teams play the national anthem. “With NBA teams now in the process of welcoming fans back into their arenas, all teams will play the national anthem in keeping with longstanding league policy.”
Hopefully Cuban fights this jingoistic nonsense. He’s got the money and the following to do so.
Yeah, I was hoping this would be the start of something. Now the NBA has shut it down.
for those that don’t know Cuban has been fined many times by the NBA for breaking various rules. I think in total his fines are over $1 million. Some of them were for bashing the refs.
This is surprising considering that the NBA is perhaps the least jingoistic of all 4 major pro leagues. One would expect this from the NFL but not from the NBA which has so publicly backed Black Lives Matter and whatnot before, including also having more fans in China than in the USA itself.
So why do we? How and why did the tradition get started?
Hoping to answer my own question, I did some googling, and found that several articles have been published recently about this very question (Mental Floss had a nice, succinct explanation, but there are others in USA Today, ESPN, et al).
The custom started during World War I (before it was officially the national anthem) and really got going during World War II.
This is a stupid fight to pick.
Stop doing “God Bless America”…absolutely.
Stop doing these silly Armed Forces week co-branding…huzzah!
Stop forcing everyone to applaud some jamoke who happened to enlist…yup.
Stop making some handicapped Vietnam vet hobble to midfield…sure.
Starting with the anthem is a losing battle. This is the equivalent of renaming schools named after Washington and Lincoln, does more to make progressive ideas look bad than it does to advance them.
Just don’t play it. Nobody will miss it.
The marriage of sports and “patriotism” has always been confusing to me. Another useless tradition.
If buying Cuban cigars in the US is so taboo, why would Cuban play the US national anthem? 
Mark Cuban has relented and will play the anthem. Whew! National crisis averted.
When will the NBA require all players to take a Loyalty o
Oath to the United States before the game too? Can’t have any dirty commies on the field, don’t don’tcha know!
It could be like that scene in Catch-22. Take an oath before you sub in, take an oath before you sub out, take one before doing a free throw, take one before each quarter…
Dallas stars have 6 Americans on their team out of 25 players. There are 9 Canadians, and players from 7 other countries. It’s composed of an international group of players. Playing the United States national anthem before their games is just stupid.
The college I attended played Division I men’s hockey and before every game, both the Canadian and the American anthems were played. There always was a substantial number of Canadians on the teams.