Here's what I pay my sub for:

1. Playing the story a bajillion times over because I like it. I play New Game+ a lot
2. Hanging out with friends I have made from all over the world
3. Progressing and gearing my character which I enjoy
4. MAP NIGHTS!! (A fun time for my FC as we get dumb and just have fun)
5. Retainers - I probably dont NEED as many as I have, but the extra space is handy.
6. Quality assurance and paying my share of server space. I know full well how much servers cost to run and maintain.
7. Friendship. I have played since 1.X alpha and this game is a part of me now with all the friends I have made (and some who we lost) from both FFXI and FFXIV. Im very introverted and if it wasn't for the developers of these two games, FFXIV and final fantasy XI before it, I doubt I would have met such awesome friends nor my spouse whom I have been married to for over 10 years now.

For how often I play this game and what I feel I get out of it. Its worth the subscription fee.