Technology+Me=Disaster...but leave me alone about it!

Alright, I should inform you that I work in a bookstore, so I encounter every type of person and opinion.

So when a male customer comes in looking for a book on a specific computer program, I show him our selection, and he asks if I know anything myself about the software; I tell him that though it seems like an interesting program, I don't use it, and frankly don't know a thing about it.
The customer then looks at me and says, "Sorry,I should've realized that asking a woman wouldn't do me any good," and then he laughed. LAUGHED!
He goes on to say, "...but you look fairly young, so you should know something remotely about it!"

Excuse me?

After giving myself a quick, mental pep talk to calm down and refrain from giving my usual "sass" (though I refer to it as merely sticking up for myself), I apologize (yes,you read right) to the customer and then ask him if he needs any more help, and when he says "No thank-you", I walk away without saying another word.

Why did I apologize? I apologized because I am not shopping, at school, with friends, etc.--I am at work. I pride myself on being polite to customers and trying to help them, and when I don't know something that they are inquiring about, I say sorry. It is just an automatic response. Surely you all understand that, right?

I did encounter some sexism though. What, because I am a female I shouldn't know technology as well as men? The only reason, good sir, that I don't know anything about the computer program is because I don't use it, and I don't have interest in technology and how it works (as long as it works for me, I am good!)--it is NOT because I am a woman.

I also encountered some age-ism, didn't I? Yes,I am fairly "young", and raised in a generation where technology is available at my fingertips, but that doesn't require me to know everything about all these new-fangled gadgets and programs, okay?

Well, that is another adventure in the life of a "Young, Non-Technological Strident Feminist". Thanks for reading!

Feel free to give your input!

-MK