The stamp thing must have lasted a little longer than that? At least around here. I was born in '63 and I remember them well. There were at least two brands. S&H Green stamps and another that were gold. I don't remember the name though. S&H had a literal brick and mortar store about 3 miles from where I live right now.
As far as Menard's; We have them here too. It was fairly slow to grow in though. The first was in a little city, that I would say is too far away to be a suburb. That one opened several years before the others. Two more have opened since, the latest right as Covid hit. I'm sure that really hurt a brand-new store.
The main two (Lowes and HD) have both carried part of each tool brand's line. I was always told that it was to reduce the crossover. That way they didn't have to price match each other. As an example, they both might sell a drill/driver kit from a particular brand, but one might have a "bonus" item, like a small pack of drill bits. This makes them have different SKUs, that way they are not the same.
In my area HD is heavier in DeWalt, Makita, and Milwaukee. They used to have more RIGID, than they are currently stocking. I don't know what is up with that.
It's been a while since I was in Menard's. Their brand was Master Force?
Lowes has Dewalt too, but not as much. They carry Bosch, Hitachi, Craftsman, and their own-brand Kobalt.