Cheetos laundromat commercial explanation needed?

Can someone explain the Cheetos laundromat commercial to me? A young woman is eating Cheetos in a laundromat. She picks up a pair of panties off the floor (presumably her own). An older woman says, "You know other people are trying to wash their clothes too." Am I the only idiot who doesn't understand what just happened? Why is the old woman mad, what is her point?