I disagree with 21kcoulter (below this post), because actually, the feathers are called "war feathers". And that symbolizes how many times they have fought for their culture or tribe. So really, the "war feathers" are actually respecting the culture, braveness, courage, and the history of the Native Americans.

Also, Just to make a NFL stadium, it costs about 850 million dollars, and to have your team rise to an elite team in the NFL, that could cost around an extra 100 to 300 million dollars. So after it is all said and done with, the cost to make an NFL team hovers around a whopping 1 billion dollars. But, back to the 15 million dollars to rebrand your team, 15 million dollars is a lot of money. And for a starter team in the NFL, that could mean the end of their franchise, meaning that they’d have to sell it, or just stop the whole franchise, and likely one other, because they would not want an odd number of teams do to schedule.

http://www.athleticbusiness.com/stadium-arena/how-stadium-construction-costs-reached-the-billions.html

My last reason exclaims that, it takes a lot of money to change everything about your school’s logo and mascot. For example, according to Allen Adamson, a branding expert with Landor Associates, it can take 15 million dollars to rebrand a NFL team. That’s as much money as about 75 Lamborghini Gallardos (which cost about $200,000 each car). Using the Buffalo Bills as an example, 15 million dollars is actually 7% of their whole net worth (which is 1.4 billion dollars). Plus, rebranding the whole team would not only costs a lot of money, it really drops the, if you will, “mini economy” for that team. Money all of the sudden drops because of taking away that not only iconic (money making) logo, but most of all it takes away mounds of money for that team. And that will break the stocks for the NFL AND that team.

Also, back to the “Fighting Sioux”, the history is what made them lean towards the name of, again, the “Fighting Sioux”. For example, there was the battle of “Little Bighorn”. In the battle of “Little Bighorn”, even though they had won their previous battle, they lost this bloody battle to the “whites” as they called (them). And after losing, the Sioux Tribe ended with a stand, proving that even after they had lost, their bravery and leadership would still live one very, very, strong. And that is exactly why the University of North Dakota chose them as their logo and their mascot.

http://www.marketplace.org/2013/10/07/business/cost-retiring-native-american-mascot

My second reason is, team does not choose it’s mascot out of hatred, it chooses out of respect or history. And in this case, a lot of teams choose their mascot out of their own history. For example, For the University of North Dakota, their mascot is ALL about history. For example, they honor the bravery and leadership of the Sioux Tribe. Also, the University of North Dakota made an agreement of using rights to the Sioux as a mascot/name. Their name is now the “Fighting Sioux”. The history is, again, the bravery and leadership of the Sioux Tribe. Plus, with this agreement from very different cultures, this unites both the Native Americans (or the American Indians as they’d like to be called) and the University of North Dakota.

http://www.sioux.org/index.php/main/inner/sioux/our_history

Plus, Marquette University chose the nickname Warriors out of respect for Native Americans. In general, mascots are chosen because of the traits they embody, like courage, bravery and leadership. Actually, 83 percent of the Native Americans that took a poll said that professional teams should not stop using Indian/Native American nicknames. Even the apparently “most offensive” mascot/nickname, the Washington Redskins, had an rating (rating of approval) of 69 percent from Native Americans across the nation. Also, it is proven that most Native American tribes like and approve of showing their identity and culture.

http://mu-warrior.blogspot.com/2005/02/why-not-warriors.html

I think it is not racist towards those people, whether it be Native Americans, African people, or people from the Asian countries. Like I said before, it is not meant to be racist towards them, it is meant to honor them. And by honoring them, we can respect them more and more. For example, when the Marquette Warriors (now the Marquette Golden Eagles), changed their mascot, logo, and everything about their spirit. Plus, Marquette university originally picked the Warriors as their name, logo, and mascot out of respect. So why did they change it if this fact (Marquette university originally picked the Warriors as their name, logo, and mascot out of respect) was stated? Also, in 1983, an official Marquette basketball program stated that, “the symbol for Marquette University’s intercollegiate athletic teams represents the spirit, dignity and strength of the name Warrior. The primary function of the symbol is to serve as a rallying or focal point at intercollegiate athletic events, while promoting cultural awareness of the American Indian.” That’s ironic. If this is the case, why did they change it. It just doesn’t make sense.

http://mu-warrior.blogspot.com/2005/02/why-not-warriors.html