One time my wife got me a really nice DeWalt jig saw for Christmas. I already had a jigsaw. It worked well enough for as much as I use it. Although the newer one was better quality and had a few nicer features.
You know what I did? I thanked her and told her how much I appreciated it. She saw something she thought would make my life a little easier and got it for me as a gift. It was a very kind gesture. If it were the wrong one, I probably would have talked to her later and asked if I could exchange it for one that would have suited my needs better while still letting her know that I appreciated what she was trying to do. I'm sure she would have been fine with that.
What I wouldn't have done was gripe at her for buying me a new power tool because I "don't like new things" or "I already have a jigsaw and it works just fine." That would be a terrible idea which would understandably hurt her feelings when she was just trying to do something nice for me.
It wasn't about the "thing". It was about the gesture. The fact that they gave you such a gift shows that they pay attention to what you do and they wanted to give you something to make your life a little easier. That was very thoughtful but you threw it back in their face. I completely understand why they're angry.