Did Jessica Simpson diss Carrie Underwood?   Jessica Simpson was spotted wearing a T-shirt with the slogan "Real Girls Eat Meat" printed across her chest — leading PETA to denounce the singer as a "stupid girl."   Simpson family insiders reportedly told OK! magazine that the shirt is a dig at her boyfriend Tony Romo's ex-girlfriend, Carrie Underwood — who doesn't eat meat.  PETA twice has named Underwood the "World's Sexiest Vegetarian."