Twitter is mainly about human-to-human connection, and that should be the presumption for any account one comes across. Other uses should be obvious, or at least declared.
I'm not sure how you separate them out entirely, I would assume that twitter knows though.
I believe the term is: masquerade.
Though mascaraed is technically correct, it just denotes wearing mascara and not to "mask" oneself as someone else.
No. The commercial in a loop is clearly recognized as such. Twitter is more like the difference between talking to the store manager on the phone and talking to a voice script on the phone which claims to be the store manager.
Good luck getting your problem resolved with the voice script. Some voice scripts are good enough that some people can't tell the difference between it. And that's arguably fine! If you can't tell the difference, then is there a problem?
But enter in the poor soul who can't get that voice script to go off script to solve that customer's problem. Or, nefariously, the voice script that can cause problems en masse because there isn't a human in the loop, or even if there is then the human simply doesn't understand that they're causing problems.