When ya’ll say pub, you mean like an American lounge, right?
If that is the case, then I would understand it not being up to snuff.
It depends on my mood whether I will send something back politely or just eat it, or just abstain. I don’t think sending food back ruins the night, if you are polite, then I think it can be done.. but if, for some reason, one is feeling off, it’s best not to.. THAT would, it seems, ruin the night.
I also tend to only pick places we’ve vetted to go out w friends or family. I also tend to support only mom and pop shoppes – places owned by families or partners (local places). I find it’s a better quality as they care more. If someone else picks, I try to stomach it anyway, to be kind.. but won’t likely agree to go there again, or will go with something that usually can not be messed up ;) Salads and desserts ;)
Still, sometimes, I get adventurous and try things I have not tried before – in a new place. If I’m hungry, I generally eat it anyway, tip them fine, and just not go back.