No no, I'm not saying I do think anyone who just wants to make me happy is being insincere, hell no. I'm just saying that if it's out of a fear that I wouldn't like them or be offended or whatever, no matter how sincere the affection or whatever that's based on, y'know, that doesn't please me one bit!!
'They' is just meaning people generally, people with whom I interact, anyone really. I have known specific people who have behaved towards me as though they feel guilty for not fulfilling expectations i didn't even have, and genuinely fearful that I had held them as obligated and held it against them that they didn't fulfill these things. I've also known people who've been at the other end of that - the people who demand duty, obligation and stuff off people just because of their 'position' in that person's life, despite that person not genuinely feeling that these expectations were fair in any way. Usually by the reasoning that this person is related to them, and hence, owes them something. But I've seen other 'holds' used, like manipulative friends who expect their friends to always agree with them, to like who they like and dislike who they dislike, who see a friend having lunch with someone they don't like as a betrayal. That sort of thing.
I'm being vague because I don't want to go into detail about people I know in RL, but suffice it to say I have encountered many times people feeling obligated by things I don't personally agree are obligations at all.
Actually one example that springs to mind right now is when I was a teenager, a friend of mine would say occasionally, in a sullen, resigned voice, "Oh and I'll have to get a gift for my Dad's birthday of course..." in a way that didn't seem to suggest she felt at all like she wanted to get him a gift, but just felt like she was obligated to because he was her father and it was his birthday, even though she had very little money at all and he already had everything he could possibly need or want. Interestingly, she tests now as ISFJ. And she'd go into town and spend all day looking around and spend the last bit of her money on a gift for her father's birthday, resenting it all the way because there were other things she'd rather have spent that money on and then when her dad got the gift it's, y'know, gone into the closet and never really been used or whatever... and I've been bewildered at all this wasted time and money and stuff over this obligation that was so unnecessary, and yet I know if she hadn't got her dad this pointless thing he didn't even want, her dad would have been offended.
I just found all of that incomprehensible. I used to say to her "for god's sake, you're only a kid, it's not like he expects you to..." but she insisted that he did, and therefore she must. For all my parents' faults, I know they never expected anything like that from me, though of course I have got them birthday gifts and they've enjoyed them. But the fact that I didn't feel obligated to get them has increased the enjoyment of the whole experience both for me and for them. But I always got the feeling with my old friend that it was just some kind of habit or ritual that they all did and it was just a drag to everyone involved, I never got any sense of the joy that I saw when I got my mom a gift and when she opened it.