Game makes you pay for:

1. Monthly sub
2. Pay for the base game (up until the most recent free trial so most people playing now bought the base game)
3. Expansions (basic full game price every 2 years)
4. You need retainers if you want decent item storage and gil making.

Yet people still think it's fine for Square Enix to charge 100s of dollars for statues, and 40 bucks for the most recent mount.
Not to mention all the other merchandise and crap they flog that a certain portion of this audience will buy each and everytime no matter what it is.

Only way they will change is if no-one buys the mogstation stuff but that isn't going to stop anytime soon.