Hmm.. It's not more messy than if you like Star Wars, Chima and Agent, they have all minifigures shaped minifigures.
I don't know how stores in the UK looks like, never been to that part of Europe. But here the minidollsets are places next to minifiguresets. In TRU Friends are placed next to City and Princess next to Creator.
They are not placed next to Barbie, Monsters High and other dolls.
Same goes for the supermarkets, LEGO has their own area.
They did a lot of test on girls in the targetgroup and the dolls were a winner, and if minidolls are what makes little girls wants to play with construction toys, why should we as AFOL complain?
The other day in TRU, I heard a Uncle tell his girlfriend about the Disney Princess set his nephew loves and which Friends set the boys has on his wishlist along the minifigureset.