I made no statement about "objective" morality. I explained my own morals, and why I'm comfortable encouraging people to blame the wealthy for the harms they perpetuate. Could you please elaborate on how you think this reply is relevant to that?
As slow as it seems to be, my perception is that societal attitudes towards wealth have been shifting over the past few decades. I'm hopeful that one day, the tolerance for their misdeeds continue to dropbenough to inspire progressively more social and legal change, as you suggested.
Public witch hunts are called "witch hunts" for a reason, and it's not a pretty one. It's also known as "mob justice", which despite the name is generally considered to be not justice at all.
It seems poorly considered to characterize social pressure as a witch hunt. It is acceptable to encourage others to share your moral convictions, there is a vast gulf between that and a pitchfork mob.
I definitely would, since the response to Shkreli has been primarily online ranting. He's never been at significant risk for physical harm as a result of the public discourse as far as I can see. I don't consider negative public opinion and castigation for unethical behaviour to be unwarranted or undesirable, so I can't see that rising to the level of vigilantism either.
In my view, society would become severely dysfunctional if we are expected to withhold our negative views of someone's choices, from fear that too many people will share those views.
This is something people often forget, nothing is objectively good or bad as they are social/individual constructs. Even things like killing or theft could be seen as good looking through the right lens.
If you want people to stop doing something, make it illegal.
If you can't muster the political will to do so, clearly not enough people agree with your view of morality (assuming a functional democracy).