Are you supportive of your partners hobbies/interests?

My girlfriend plays badminton every Sunday, every three months or so they have tournaments.
I don't play, never been of interest to me, I play football Wednesday night and Sunday morning.
She's invited me to come along to play a few times which I've declined. I go and watch her tournaments when I can and she comes and watches the occasional Wednesday night games.
After a strop, she moaned that I'm not very supportive... judging by this situation alone I can't see that.

Please tell me if I'm missing something here!