You know, I haven't really thought about it. Although ... I went over to the kids section in the library to look for audio Potter books and that was abit wierd. In my old library YA books were near to adult SFF, but in the library I use now the kids books are all the way at the back of the library (so that if your baby starts crying you have to traverse the whole of the library to makes sure not one single person is left undisturbed.) MAde it rather obvious that I was going to look at YA books
I don't like the thought that people know what I'm reading, but I've not ever had a problem buying YA books. Indeed, when the last Potter book was released ~ I was there. WH Smiths. Midnight. And it was glorious. Okay, so mostly there were teenagers standing around in the queue and nine to twelve-year-olds with their parents (or parents with their kids?) but i know for a fact that at least two of my mates were also queueing up for the Half Blood Prince.
And half the time it's hard to tell when something is YA ~ both Eragon and the Black MAgician trilogy are displayed as SFF in my library and the second Robert Carter book is displayed as historical ~ even the the first book is in the SFF section
So I guess that if someone is rude enough to sneer at you for reading a kids book, you can just claim that it's been mis-classified.