In a 2013 study of undergraduate women, one-third identified themselves as "princesses." They placed a higher value on the physical attractiveness of a mate, were less likely to want to join the workforce after college and were more likely to say they wanted to marry a breadwinner. And when all the women were given puzzles to solve, the "princesses" quit faster.
(This study, a conference paper, is described and cited in this paper, co-authored by Sarah Coyne, which similarly showed that girls who preferred playing princesses showed more gender-stereotyped behavior a full year later.)
Researchers haven't proved that all little girls who like tutus will grow up to be entitled quitters. But play does prepare children for life, so boys and girls both need broad options, says Rosemarie Truglio, a developmental psychologist and vice president of education and research for Sesame Workshop.