Part of the reason for a defensive explanation for using film may be because digital people have given analoguers some grief, one way or another.
One day out shooting, I had some guy using the very latest techno-marvel DSLR ask me why in heavens name would I still use film? He really made an issue of it, telling me about how much better digital was, higher ISO, etc, etc, automatically assuming I'd never held one in my hand.
When I told him I shoot all my colour with a DSLR and all my black and white on film, he started up again about how digital could make great B&W pictures, there was software for that, etc, etc. Actually, HE seemed to be on the defensive.
This was certainly the most extreme situation, but not the first, and won't be the last.
It's funny though, virtually every person like that, (all men), were in North America, I can't recall a single time here in Europe.
I can honestly say I've never walked up to a complete stranger and asked him why he uses digital, and start telling him how much better film is.
I have a large business-style calendar on my desk, full of notes, reminders, lists, ideas for automotive articles, and the odd appointment. A number of people have wondered why I don't use the Google or Mac calendar, instead. It seems if something isn't done electronically now, it's not as good, out-dated and inefficient.
Anyway, I tell them I like having it on paper in front of me, and then point to my package of 3B pencils. That really appals them.