Not to scare you, but even your every word typed can be a liability. The internet lives forever, and we have all traded our privacy for the joys of interconnectivity. Not that it is easy to uncover blind aliases, but I'm sure an enterprising reporter/investigator may have their ways. More likely it would be someone you knew either intimately or tangentially would 'out' you if they thought they could gain by it, or spite you.

However, living in fear is no way to carry out one's life. And as for public events, that's what masks are for (or hoods of you or yours are so inclined)! And if you're outed, at least you'll get the BDSM vote!