At this point I just collect collectibles for the sake of it. It’s nice to look back after a few years of participating in events and see that you now have a line up for that holiday/event. Mismatched and all.
I collect the collectibles that I like and that fit my aesthetic :3
Other than that, I usually take part in the events to ear the currencies and then sell those collectibles in order to be able to get collectibles that I want.