Saying Chiefs is not like saying Generals for the most part. In almost every single circumstance, it is cultural appropriation. Point blank.
Kansas City Chiefs- logo shaped like an arrowhead = cultural appropriation
Cleveland Indians (say no more... however) their mascot is named Cheif Wahoo = cultural appropriation
Chilliwack Chiefs- Logo, and former mascot Chief Wannawin = cultural appropriation
The Whitley Warriors, seemingly harmless name right? Warriors could be used in all kinds of different contexts... until your logo looks like this: https://goo.gl/images/Dgqy6V
Another side of the coin:
Oshawa Generals - Mascot - looks like a bear, logo NOT RACIST/ZERO cultural appropriation
See the point? It's the name and what follows after that. It's the context, Chiefs, Braves, and Seminoles may not be considered derogatory UNTIL a bunch of white people improperly use an entire culture that isn't theirs to use and exploit it for millions of dollars along with not understanding WHY IT'S FUCKING WRONG.
Remember last time a flock of white people took what wasn't theirs from indigenous people...?