Oh my god, non-regs in a multiplayer game? Welcome to the internet!

In all seriousness, go play one of all the other games out there (let's say, a round of InstaGib on QL; or jump into a T1 duel-server), and you'll be able to see exactly the same. It's not a bug, it's something that's caused simply by how multiplayer games work. It might look like your shot hits something on your screen, but it actually doesn't. It's a bit more obvious to some in FE:L, as the LR/LRII spawns a beam, not a projectile like the other weapons. If this beam hits, you'll see the typical explosion. This explosion is handled client-side though, and will appear even if you haven't actually hit something (it's enough that your system
thinks that you've hit, so to speak). But, naturally, you won't ever see this kind of behaviour if you're hosting. Just try it. Also, this problem will get more and more apparent at higher latencies.
Bottom line: If you see a NR, you have not hit anyways. So it's not that you did miss
because of the NR. That's an important point.
Edit: By the way, the name of this phenomenon is somewhat misleading, as it actually does not describe a hit which did not register, but a miss which looks like a hit on your side.