Why has the Lego Friends (for girls) line prompted outrage while Legos intended for boys didn't?

When Legos were initially invented, they were considered a gender-neutral toy. However, in the last few years, the company has made a strategic business decision to market to boys that has been highly lucrative. I do not recall hearing any public outcry over that decision, but please correct me if I’m wrong.

Recently, Lego announced a new line of toys called Lego Friends, clearly (although not explicitly) intended to be marketed to girls. Many people seem displeased with this choice on their part.

What do you think about this? Why are reactions so different this time?