Wouldn't it be nice to play a game and know that if your opponent breaks a rule that the Referee will call him out on it and then administer the penalty accordingly?
The NFL knows that their ticket to high ratings is great quarterback play. The NBA knows their ticket is Stars, and it doesn't really matter at what position. The more charisma a Star player has then the more money and interest that team will get.
The NFL protects the quarterback by going over and beyond penalizing an opponent who may damage the #1 product, the Quarterback. When it comes to the on the field rules such as fumbles, completions or yardage marks, there does not appear to be any favoritism in the general sense. It also does not appear that pass interferences or holdings matter on the players involved. They are an equal opportunity penalizer.
The NBA is a different beast on officiating. There appears to be a Tier. The higher you go on the Tier the more rules are relaxed for you. I remember Lebron while at Cleveland litteraly running from the 28' mark on the sideline and then dunk the ball. I cannot even count how many steps that was. The Crab Dribble (please!). The #1 complaint I read from bloggers on this site during the Olympics was the amount of Travel Calls were being called against the USA. Unfortunately, only in the NBA do you get away with that much traveling unless you do the Akeem the Dream Jump Step. The jump step is a good example of how a Star is treated on an NBA floor. If you do it so much and get away with it they will actually change the rules to make it legal. The jump step takes 3 steps to accomplish but since you land on the court with both feet simultaneously they only charge you with one step. Akeem made it so popular that the NFHS, National Federation of High School Officials, made it Ok to do.
How many NFL Referees can you name? How many NBA Referee's can you name? Some NBA Referees are Stars or think they are Stars. Heck, most NBA fans know these Referee's better than alot of the Coaches and can tell you their tendancies of what fouls they will call and against whom. The only NFL Referees I remember their names is Ed Hochuli, 61 year old muscle builder and Jerry Markbright, my favorite who did all those Superbowls.
So the NFL will go overboard to protect a quarterback with their interpretations of head shots, low knee hits or questionable roughing the passer calls. All other rules they try to enforce equally to all players and teams. The NBA will turn a blind eye if your good enough to traveling and foul calls on their Superstars. (Do you ever wonder why great teams always get the calls against the Washington Wizards? They need a Superstar or two!).