No one can ever be different than they are. The question is merely one of how they play the “game”. Different environments suggest, and sometimes require, a different “gaming strategy”.
What we are witnessing from each other is the gaming strategy results. Of course that implies there is some “winning” to the game (which seems to apply to Old_Gobbo anyway). In most cases, the only winning being sought is very minor and in very many cases is merely “playing around” without concern for any gain or damage to others.
Online one can be very inconsiderate, cruel, and careless. Sometimes they perceive no harm, so they play with gaiety. Others maintain their demeanor, concern, and respect for the needs of others and thus display something more alike to their real-time persona wherein it is more obvious when damage takes place and threats for being inconsiderate are more apparent.
The perceived freedom to act on impulse is much higher online. Disrespect is prevalent and without regard - until threatened by alert mods. “Why not?” is the underlying thought.
Such behavior reveals a little more of the underlying impulses within people and tends to present a picture of a character framed around only more hidden components of their entire personality. It is similar to “first impressions” in that it is easy to believe that you have perceived more of the person than you really have.
So the difference is not merely one of the players exercising different personas, but also the observers exercising free judgment - “Why not?”