You're not out of line it's just how you feel, registries just tend to really be less stress on all parties. Places that don't do registries as a normal likely don't have this feeling. I don't think anyone mentioned anyone feeling mad. The conversation was about understanding someone's taste level if not going with the registry (which that helps to know what they want), someone mentioned getting the established thing. That's a highly personalized gift such that you would want to make sure they actually want that. It's etched with a last name and a date. Taking that to good will would be a tad pointless in that respects. And for me my last name isn't my husband's so in that case it would personally (so I'm not asking others to feel the same way) feel weird. For that reason I haven't bought anything like that not a monogram flag or anything else.
Sorta off topic but sorta on I remember that on our registry we put noritake colorwave sets but in all different colors. I loved the idea of mixing and matching all these beautiful colors together. We purposefully put a wide variety of colors and only 1 (or 2) quantities of the same color. Each set had a dinner plate, salad plate, bowl and coffee mug. The price point I want to say back then was maybe $40 or so so it was economical for many. When we ended up opening those gifts (which I think we did the bulk of that after the honeymoon because we left the next day after our wedding and gifts were still being mailed during that time) I remember some people who I think were more traditional in their thinking buying us 4 sets of the same color likely thinking "oh no they surely want matching sets" We ended up returning some gifts and exchanging others and for those dish sets in particular we just exchanged for other colors. Sure 4 reds might seem nice but I liked that I have red, black, green, teal, blue, brown, etc
So even with registries sometimes people take what they think they would want and get that for the couple. Registries aren't perfect either on that front.
Regardless gifts are always appreciative sometimes the giver goes a bit more into what they want though, it happens to us all.