The lack of politeness is not just confined to Genes, it happens all over the place, including on forums, mailing lists and Face Book.
I use "A" and I am not exaggerating when I say 4 out of 5 people to whom I've sent information and/or media never thank me. In fact recently the only person who has bothered to thank me was someone whom I could not help.
I'm also fed up with the standard of messages I receive. Many are very poorly constructed with so little identifying information I have to write and ask to whom they are referring. I recently received one with just a surname, a common one at that!!

I've even had opening messages demanding a gedcom of my tree with the qualifying statement .... "so I can add it to mine"....all this before any link has been established

Many are so rude and demanding and amount to little more than "You have what I want, give it to me NOW" ....no please or thankyou's included of course.
None of that type of behaviour makes me want to willingly share