Nope. It's totally irresponsible. Given the power of the internet and the ease by which information spreads, the real potential is there. And even then, it makes no difference.
Publicly (or to their face) calling a former employer "sleazy" is very, very unprofessional. It demonstrates poor taste and lack of restraint. And ultimately, self-importance.
"How dare they not recognize that their pathetic company is NOT my dream job? How dare they offer me money to continue to support their petty operation?"
Are you people even serious in defending this?