Oh Seed, I am sooo jealous!
Not only of your (past) plant pot supply, but of how well organized your work shed is!!!
I tried Wal-Mark, Lowe's, Home Depot, even a small nursery just a block from my home. The big boxes all said they need the pots with their SKU stickers to get credits from the growers, and the small nursery said they recycle them all for new plants out of their farm. SIGH. So, at least to find some that were $1 and not have the $50 shipping charge associated with getting them delivered by nursery supply ... am very, very happy to finally have enough to get my seedlings in better growing-sized pots.
I do think you are right that everyone should check around first ... I did score about 10 free ones when the city was planting stuff in a local park, but even they were hesitant to give them up. I think the suburbs here are just very tight with items and need them to verify work-done, losses to be reimbursed, etc. And, the craig's list/freecyle ones that have come up have just been too far away (same cost in gas to get there and back).
Hope you find a great new place that will hand them out again ... it gets really expensive, really fast, just to find pot-homes for these babies!