Oh god this.
I’ve started to lie about this at weddings now, it’s just not worth the hassle.
At a wedding last weekend the guy to my right said “you don’t to justify it, but why are you vegetarian?” to which I just replied (a bit rudely, tbh) “I’d rather not mate, cheers”.
Then the woman to my left picked up on it and told me that if I was going to be vegetarian I had to have a reason. I told her I didn’t. She told me I did. Fucking cunt.