I've washed four sweaters so far, dried them on the racks, put them in plastic bags, and now they are in the freezer. I've started on the next batch. I can't do too many at once because of sweater rack limits as well as freezer space.
I don't think I have moths but it may just be that I have taken such care. I have had things ruined from moths in the past and really hate it when something that has cost me a lot of money becomes a really soft, beautiful rag...sometimes with sentimental attachments!
Taking care of what I have is cheaper than replacing it, even if I have a way of replacing it.