I think some people do it on purpose for their own strange reasons.
My mother does with people or situations that make her feel insecure. Her cousin always made her feel less than and insignificant for example, so she always pronounces said cousin's daughter's name wrong. I don't think she's even aware she's doing it. I don't even think it's malice of any kind, just a subconscious way of feeling she's getting one over on someone. Pathetic but it happens. As another example, family friends moved to Indonesia. The wife tended to make my mother feel insecure (not the woman's fault, she did nothing wrong, it was all about my mother's insecurities), so she always talked about them being in Thailand. She's a intelligent woman who has travelled. She knows Thailand and Indonesia are completely different countries. I would correct her every time but she just kept doing it. It never happens with people she seems relaxed about.
So anyway, that was a bit of a long winded way of saying I think it's more about them and nothing to do with your name or you.