Welcome to Flyertalk
QueenofWands. The gown in the link is just lovely. If the slobs can wear what they like (and they do), why can't you wear such an elegant gown? Just be aware that you WILL be the belle of the ball. Except for opening night at the Met, one rarely sees anybody in formal attire for any performance whether it be the theatre, ballet, opera, or the symphony.
Have a wonderful time.