Yes, I have such experiences, and even now experiencing.
Way back in 1980 when I had to go to Chennai for attending the induction training for my job, I met a family as directed by relatives in case any help is needed. As I was going to Chennai for the firs time they took this precaution. But I did not need their help as my employer had arranged for my stay and other needs. But still for courtesy, I met the family and visited them once or twice on holidays.
The younger son in the family appeared to be different. One day he met me near my training place and in the guise of forgetting his purse and some need he took some money from me in private. I did not make it an issue even when he did not return it. Another in front of his parents he said that he told me about his birthday and I promised a gift to him. Needless to say, I had to buy him a birthday Gift- gift card then.
I usually keep low profile and do not announce or publicize my birthday, wedding day etc. As I am not active in social media like FB ,that way also people do not come to know my details. But I have a friend who always tom-toms his DOB, wedding day, grand child's birthday, and anything where he can get gift, compliments , greetings and wishes, and even the common 'likes'. Some days before or just the previous day he will say directly or indirectly so as to remind me those days. Naturally for the sake of courtesy and keeping with my habit, I will convey greetings and best wishes or as per the event and context give gifts.
But till this day, this friend has never ever asked me about my DOB, ,wedding day etc.
The same friend will ask without hesitation for any help he needs from asking for clearing his doubts on some matters to hospital visit and attending when he or his family member is not well, The irony is that he may not tell others the help given to him but chest beat how he managed things.