We were a very tightly knit guild pre cata. We didn't all call each other by our real life names but many sub groups did. We did a dozen real life meets so eventually some of us started using IRL names, also using IG names IRL .
Was sometimes awkward when we had new recruits because they wouldn't know who we were talking about so we tried to keep IRL names only during non important raiding conversations. So no people calling me by my IRL name doesn't bother me, I kind of enjoy it actually, shows the person speaking to/about me shows some form of interest in me, I was not just a slot in the roster.