There's never one reason for something in the NBA. The Sixers don't lose because of one player or one play, just as they don't win in the same fashion. The same holds true, philosophically, for why the Sixers do not get to the free throw line enough. It's on the players, the coach, the system. But it most definitely is not on the referees.
The Sixers only attempted 10 foul shots in the Festivus loss to the Brooklyn Nets. BK took 30. That prompted Doug Collins to paw the ball of arson after the game, tempting fate by alluding to referee unfairness on the discrepancy. He claimed he wanted to keep his holiday money, so he didn't unleash any venom, but it's definitely clear that he and his players feel like they're getting shafted by the refs.
Why? Lack of a superstar getting superstar calls? That may play a role. I don't think it's the end-all.
Doug Collins, as we know, coaches his team to avoid turnovers (2nd best TO rate in the league) by limiting most risky takes to the basket and dangerous passes. That results in a team sitting in the bottom five of shot attempts at the rim and the 2nd lowest free throw rate. On the flip side, they're near the top in number of attempts from 16-23 feet, shooting 24/game despite only shooting 34% from there. And they're even towards the bottom in threes attempted per game.
It's no secret that Collins loathes turnovers, but ball security at such an extreme level is clearly coming at the expense of the team's ability to create quality shots. Again, the Sixers find themselves at one end of the spectrum, and again, the Sixers are struggling offense because they sacrifice the ability to seek out good shots in order to keep the turnovers down.
Basically, Doug, you can't blame the refs for not calling fouls when you have Spencer Hawes flaring out for long two after long two. Evan Turner goes games without taking shots at the rim. Jrue Holiday settles as much as Nick Young. The philosophy is not working. It's the opposite of what should be done.
Personnel has a lot to do with it, but I'd argue that it's about desire more than anything else. If you want to go to the basket, you go to the basket. You'll turn the ball over, you'll take a few wild shots, but you'll have a better chance of succeeding (they shoot about league average at 65% from the rim) because you're going to draw contact. Even accidentally, you'll find yourself at the line more.
I was at the Syracuse/Temple game at Madison Square Garden a few days ago and I watched Michael Carter-Williams and Khalif Wyatt continue to attack the rim. MCW had a mismatch on him and would just go right after it. Khalif used a variety of savvy long steps to get better angles on the basket. Obviously, it's college and the game is vastly different, but you see guys that aren't super athletic going at the rim because they want to.
This problem stems from the coach's unwillingness to change his offensive philosophy as well as some outright laziness from the guards. It's equally problematic that the Sixers don't run many bigs on the baseline so even when the guards do drive, they don't look up to beat the rotation with a pass inside for an easy bucket. Only about 50% of the scores at the rim are assisted, a mark near the bottom five in the league.
Don't blame the refs for your problems, Doug. Sure the personnel isn't perfect for... anything... but you're not using them correctly anyway, so stop pointing fingers. Make them take the ball to the basket. Make your bigs play inside more so when a drive draws away the defender, the guard can beat the rotation for a quick shot at the rim.
The same thing happened last year. Low attempts at the rim, low foul shots, low threes. This year they don't have the defense to make up for the lack of offensive intelligence. Failure to change the way the offense is run will result in more and more losses.
Wake up, Doug.