We were 5 adults and didn't feel odd at all at the PSB! The people around us included 3 tables with small children (boys and girls) and 4 that were only adults! One was a single woman, who brought a book to read while she dined. I'm confused about the comments about the little girls... not at all our experience!
We LOVED the PSB, and the princesses, but I must admit none of us care about any of the other characters, like Pooh. Just the face characters. =) As teenagers, we only did face ones too (Mary Poppins and Alice at 1900 Park Fare) =) Guess it depends on what you want...
We also enjoyed the food! Wonderful experience all around, and we got great pictures!