The manners of some people

I shall start with a conversation I had with my brother, nearly two weeks ago. I rang him to enquire as to whether he liked the singing style of Cleo Laine. He said he did, but asked why I wanted to know. I asked if he had a record player. He said he did, but again asked why I wanted to know. I said I had been given some of her records, and wanted to know who I could give them to, as I am not a fan of her style of singing. I admire her talent greatly, but she doesn't 'send' me. I asked him what he was doing, as he seemed more distracted than usual when I ring. He said he was mucking around on his computer. What is so unusual about that you may be asking? Nothing, apart from the fact only a couple of months ago, this same man had said, he didn't know anything about them and didn't want to know anything.He was having a ball! I asked him where he had bought it, and he said from the local High School, and it had cost him peanuts. Later that week, I was talking to my daughter Deb. When I mentioned about her uncle having a computer, she asked if I would make enquiries for her as to the availability of any more. I duly did so, and was told they had three more, but the hard drives didn't work. I was talking to my son about it, and told him I had been quoted a price of $1,500.00 for a new HDD. He said that was ridiculous, and told me he could get one for a mere fraction of that.
I went into the school yesterday morning and told the receptionist, that if they had a computer that needed a HDD, and they were prepared to sell it to me as is, I could get the HDD myself. She went to ask the teacher about it, and came back and told me I could take it there and then. I was quite surprised, but very chuffed. I was not expecting that to happen so soon.
I went in to pay for it this morning, and ran into the woman I had phoned about it. I think she is on the school commitee and said I had my computer, with the sole purpose of letting her know that I had it, so she could take my name off the list. She then proceeded to let me know that it was not meant to be mine it was meant for someone else. Intimating she thought I had jumped the queue! This is NOT the case, as that is one of my pet hates.
She continued to heap coals on my head, at the same time agreeing with me that it was not my mistake. If I had been in her shoes, I would not have said anything, being very concious of the other person's feelings, and not wanting them to feel bad.
This is the bad manners the title refers to.