Good idea. I can see a place like that doing well. I can totally see this as an edgy, fun, come on in and take no sh*t kind of establishment that could easily draw in customers of several age ranges.
But these girls are trying so hard it all looks and sounds phony. Put the megaphone down if you can't stop screeching into it so loudly, your words are squeaky, incomprehensible, high-pitched explosions that are spaced just enough to make hearing a full song on the jukebox  impossible.
I'm a grown woman. If I order a vodka and club soda, drink two of them, can taste no vodka, and walk out of there without so much as a buzz, then it's clear you're diluting my cocktails (aka stealing from me), and I will never put my money into your establishment ever again.
Good luck.