There are two lines of thought here and while I tend to agree with you, I can also see the other side of the coin.
Does every good deed have to have some kind of reward? What is that teaching our children. To always expect something in return for doing something for others? It's just a little too greedy for me
Honestly, I was brought up, as I am sure you probably were too, to write a thank you card for a gift or for kind actions. It was part of teaching us manners, not to expect something in return. But the reality is, not everyone is taught that or teaching that anymore.
Unfortunately, some parents don't instill in their children the simple affect of a thank you and expressing gratitude. As teachers, they have seen this over the years and you may be able to go back to a time when they didn't encourage the gift or act of gratitude. If the parent doesn't teach their child to express gratitude for kind actions, then where will they learn it?
I'm sure most of us are intelligent adults who know when to be thoughtful but the reality is, there are those that have no clue. I'm sure it is meant for them, not you.
I wouldn't take it personally and I most certainly wouldn't look at it as being forced. You were going to do it anyway and for the others, think of it as a gentle reminder that manners still matter. And I think we also need a reminder that gifts don't have to be purchased. A flower picked from the garden or anything else their creative mind can design can be a gift. It doesn't have to cost money.