You are correct my friend. I had about 1000 miles on my Dunlops. I think the most they'll give you is $50/tire for a trade in and they'll even try to give you less. Stand your ground... hold your breath if you have to.
If they won't match the price just for asking, ask them if they'll match...
BFG AT
I bought a a complete set of 265/70-17 BFG AT's from Discount Tires two weeks ago. I told them that someone quoted me a price and wanted to see if they would match it. They did! I paid $686 for a set of BFG's. I believe the price was $165/tire minus $50/tire for my stock Dunlops.