I believe this to be an early S&H Green Stamp but I'm thrown off by the reference on the stamp to "discount stamp". Did that mean the same thing as a trading stamp or was there some sort of store discount represented by this variety?

Also, here's a series of Merchants Green Stamps. I never heard of them before (probably from another area of the country than where I live) and assume they were just a competitor to S&H Green Stamps. Can anyone identify where (what area of the country) they were prominently used?
