Maybe her mum understands that whatever Taylor does, all the antics and shenanigans are only a part of an act. Maybe the "real" Taylor isn't really the person she tries (too hard, perhaps) to make everyone believe she is. She'll rake in the moolah and the all the much desired publicity, which really is all showbiz is about, innit? Both fashion and Hollywood aren't strangers to nudity, so don't exposing your gaffer-taped tits or barely covering your tits on the cover of Vanity Fair or Vogue Paris cover sort of boil down to the same thing, really? That's the only logical explanation I can come up with as to why her mum would be perfectly OK with her gigs.
The other obvious conclusion one can draw is that they're both avaricious, money-obsessed scumbags who don't give a toss about really anything else.
And all that's best of dark and bright
Meet in her aspect and her eyes