They specifically BANNED jeans, they did not BAN dress pants or jumpsuits. She has a point.
They also didn't ban 1890s swimsuits or togas. Does that make wearing those garments ok? No it doesn't, because words have meanings; it's really that simple.
My guess is that mom, and probably her spawn, wanted to get turned away so they could go "viral" and get simpletons to rush to their defense.