Yes I’ve def been on the receiving end of this, in both the tech sense and in a way similar to Willy’s comment about his daughter. In my case it is when I came to buy a new car and my friend (male) drove me to take a look. When the sales people come over they invariably talked to him about the details even after being told from the start that the car was for me. We either asked them to tell me as it would be my car, or let him tell them he had no idea what they were talking about and had no interest as the car was for me.

The worst case I had in IT was when I went for an interview as a web developer, and was told at the interview that the reason they had decided to see me was they had never heard of a female developer! I wouldn’t mind so much but this wasn’t a small firm it was an ISP.