I'd have no problem with televising executions. In fact I believe they should be. If we as a society are unwilling to accept the blunt truth of what capital punishment entails, then we shouldn't have it. However, charging money to see an execution? I think not. Certainly not for the purpose of making money for a private enterprise.
Our society is so desensitized to that sort of thing that I don't think it would much matter. Watching an actual life be extinguished, whether it is from someone guilty of a horrible crime or not, just doesn't have a lot of impact on people when they're watching on TV.
But no, it's a bad idea. Pretty sick, actually.