So on reading this comment I was like, "oh, I see, Arby's, like RB, roast beef?" Except on looking it up, that's not the explanation! "Arby's" does come from the initials "RB"... but it doesn't stand for "roast beef", it stands for "Raffel brothers"! Rather less obvious.
>Friends that worked their described the "beef" as being a weird loaf of pressurized mewt-like protein before its sliced
It's just deli meat. Arby's is extremely open that their roast beef is deli meat roast beef. It's no different from what you find at the deli counter in your local krogers.
Have you or your friend never seen deli meat before?
