sure, but it doesn't work. that's why companies give out equity and options, instead of trying to blackmail their recruitment targets. and startups around here described as being run by a bully implode or close soon thereafter.
I wish I could say the same about NYC startups. I once worked for a place where an employee left to a competitor which infuriated the CEO. As a result he had a meeting threatening to track down anyone who left and get them fired. In addition he made everyone sign a non-compete agreement or risk being fired. This startup is still around and doing just fine. I've heard similar stories from other nyc startups.