The thing about someone signing up with multiple accounts is that it makes the exchange more vulnerable to whatever's going on in that person's life. If I sign up once and then get hit by a bus, that's one pinch hit the mod has to find. If I sign up twice and get hit by a bus, now the mod has to find two pinch hits, even though only one person got hit by a bus.

The mods are the ones who are up a creek if something happens to you, so I think it should be up to them to decide whether they're okay with that additional risk. If mods say socks are okay, then they're okay. If mods say no socks... then IMO you shouldn't sign up with a sock.