Why does Kelly wife say, "they left all the weak ones here"

Curley's wife says, “They left all the weak ones here....," when she roaming around and meets up with Crooks, Lennie, and Candy in Crooks' room. Her comment alludes to the fact that all of the men except for the old man, the black stableman, and the mentally challenged have gone out. Thus, they left the weak ones (not real men) behind.

They were described as animals