I have been to a wedding where the food was so bad a few of the guys went out and brought back some pizza - people were ducking out and eating it in the parking lot, lol.
I think the bride and groom are selfish to think only of their tastes when feeding their guests.
Every single other thing about the day is all about them and their tastes and their colours etc etc...when you are hosting a gathering you should take others into account.
People are attending your wedding, getting babysitters, buying you gifts, this should be a pleasant thank you for the guests. Even if you are vegan you can offer wider choices - its not like you are making it, handling it, or eating it yourself.
Bride and groom should suck it up and be proper hosts.