If someone brings me a gift, whatever it is, I graciously accept it and say thank you. If it’s from my mom or husband and I won’t use it, I’d tell them I want to exchange it, but I would not say that to just anyone. On rare occasion I might drop a hint about something I would prefer so they don’t gift me the same thing again, but not in the moment of receiving the gift. It depends on who gave me the gift.
If I’m at the table and someone prepared a meal and I really hate an item that was prepared, I would pass on eating it. I’m sure there isn’t just one item offered, so I’m sure there is something I can eat. I don’t drink wine when it’s offered. I don’t eat the cheese and crackers put out for the appetizer. I don’t want ranch or blue cheese dressing on my salad, I’ll eat it no dressing if necessary. I’m not choking any of that down. Well, maybe a plain cracker. I’m also not eating mayo soaked potato salad or mayo cole slaw. If someone cooks me something very bad for my health, I’m only taking a sliver, and only if I like it. I don’t take a drag off a cigarette if offered, and I don’t eat fatty, greasy, cholesterol ridden food if I don’t at least like it. If I’m going to clog my arteries it’s at least with foods I like.
I don’t want someone to waste time and money giving me something I won’t ever use or eat. If there is a chance they are going to do the exact same thing again in the future I’d possibly do something to try to prevent that from happening. It depends. If it’s something I can easily regift I’d probably refrain from saying anything and just say Thank you.