I don't really see the hate for these people. You get the chicken pox once. The earlier in life you get it, the less troublesome it is.

I'm not going to argue against vaccinations, but the reality is that we have much more long-term data about having kids play together than the chicken pox vaccine. Both options are probably equally good at this point, and most people have personal experience with the first one and not the second one. Therefore it's not particularly odd to want your kid to get chicken pox naturally.

(I don't buy the argument about "giving the immune system a workout", though.)