There's still games where the prices are a little bit lower; try checking out non-weekend and non-marquee matchups.
Unfortunately it's mostly on weekends when I get up to Boston.
For instance I'm going to be in Boston the first weekend of November for a wedding. I just looked at the Bulls game on Friday 11/5, and there are two seats in the very top row of Balcony sec 327, and they are $90.25 each with fees. I just can't justify spending $180 for my wife and I to sit in the top row of the balcony.
If the seating chart is accurate and the game is almost sold out then the team knows what they're doing, and they're maximizing revenue from each game. I can't blame them for that. I personally just can't imagine spending $90 to sit in the top row of the balcony for a regular season game.