Note that here I do not say "gentlemen."
Look, it's really not that difficult to learn to tie a bow tie. I haven't done one in a while, but I'm pretty sure that, given about two tries, I could produce a respectable butterfly. Also, pre-tied ties are extremely obvious even to the casual observer, and make the wearer look like an infant.
Furthermore, though I abhor the wearing of four-in-hands, Windsor knots, etc. for dinner dress, these styles are now widely accepted, so there is no reason ever to wear a bow tie if you are for some reason incapable of tying one.
Because you are five years old.