I did too, but found that the betta plastic containers are the ideal size and the lids have the appropriate holes in them already (to keep out fly larve), and are stackable while still allowing the airflow with the holes in the lids.
I culture micro, Walter, and banana worms. Pays for the blackworms for my larger fish at the LFS so far
and some other hardware every now and then. Plus enough to share with some local fish keepers.
Guess I'll keep looking.