There are a lot of gyms in the South and off the coasts who are making a hell of a lot of money copying the going rates of the trendsetters on the coasts.
I paid $80 unlimited in the rural South at a very reputable gym. I bet they're charging $150-180 now, because they can get away with it. There is no justification for that cost increase, as the gyms that charge that value have substantially higher costs. However, it makes sense so long as they are planning for a future where the popularity of bjj/mma dies out. Rural/low pop areas will be hurting in that scenario.
Still, the internet is full of bs. I have seen posts regarding prices of gyms I've trained at that were just baloney. For example, on the UG, there was a thread where an individual claimed my current gym costs $90 more a month than the contract specifies. There are two primary reasons for such inaccuracies:
-competitor lying and driving away business
-guy who never came in is creating an online excuse for not training--justification through the old "they charge so much, it's not worth it."
One additional excuse comes from the gym itself, but you almost never hear about it--the gym inflating their fee for douchebags. I've heard of it happening at different places I've trained at, so it is likely common.