I just order them from amazon.com as I don't want to deal with color shifts on refills or no-name brands. However I have used Amazon's own print carts where it was non-photo work.

--->> But you are right. Drugstore prints are often cheaper than printing at home. You are paying for convenience at home and even at 1/2 price the last time I did the math, the walmat/drugstore was still cheaper.
Bob