If they are hatchery or feed store chicks, they are more properly called production reds and Easter Eggers (EE's.) Production reds will often get some white or black feathers, and will be a much lighter color of reddish brown than breed standard RIR's. Read about the difference in our breeds section -- and see pics of RIR's and Ameraucanas that are closer to the breed standard. If they were labeled "Americauna," that's a giveaway right there, since there is no such breed. Production reds I believe are usually a cross between New Hampshire and Rhode Island Reds. Easter Eggers are also a cross, and I believe usually have some Ameraucana or Auracana in their background. (I don't know much about breeds.) You would pay more, often considerably more, to get show quality birds that more nearly represent the breed standard -- if you can even find them locally.
Lots of us have hatchery flocks, and they still lay great eggs, are lots of fun to watch, can be pets, etc. Hatchery birds are bred to lay particularly well. I have the same two types you have, and some others. I used to get gorgeous blue eggs, and one of my two reds is just full of personality. And, these breed names are commonly used by all the big hatcheries; it's not that you "got taken" by some small operation, at all. They're perfectly good chickens, they're just not show quality.