Sex does sell, that's a proven fact, can we blame companies for giving us what sells? Tempting to, but really we just need to stop buying.
Well..I don't think that if it sells, you are allowed to do anything, right or wrong. Selling by sex is manipulation as I see it, rather than selling on the quality of your product.

I agree that girls should not learn to 'sell' their dance as sex, it is more than enough that they are good at it.