Nobody is forcing anyone to pay anything, but if they didn't update the graphics until now I don't see them doing it for free, as it would require a lot of work. The team currently working on FFXI is pretty small right now, and they would need to get more designers and programmers from SE for sure, which has a cost.
We have payed a lot of money and invested a lot of time in this game, I've been playing for 11 years now, almost non stop. Our money went on updates, expansions, servers and what else, so we basically got what we payed for. The point now is asking for something that they didn't plan, as they would most likely continue with the regular updates till the game dies.
That's why I believe we could really help them out funding the project. I just hope they are discussing about this within the team right now, they should respond to let us know what they think.