@Salixj Could it be a "female" thing? We are socialized (by example and teaching) to not be pushy or demanding but helpful, social and shy.
I happen to use equal wordings and receive no help, either. Another pattern of mine is to use "we should" instead of "you do" to order my husband to do something - which he doesn't since I said I could do it, too...
(Older but interesting topic.)
I recognise this, it was happening to me in the past too. I would rather think these formualtions come from you speaking/thinking in several different languages and freely (unconsciously?) transferring idioms from one to another. Of course I can't know from your profile, but I am immersed in such a context and I hear people (especially children) saying stuff like this often. It can always be traced back to something else in the other mother tongue of theirs. So the question is this: do you speak fluently another language (mother tongue?) in which the literal translation of "if you'd be so kind to hold the door for me?" makes sense?
@Salixj
I just realised the funny one I find myself (and people around me) still doing is this: "I would like to ask you to ..." - and my inner self immediately screaming: "you wouldn't like! You are just doing it!"
@blueplanetslittlehelper