A man I know said it was really unfair I get a pension check and he doesn't. I laughed and said, "It's fair. I got up and went to work and you never did that."
"I spent my life working for the revolution."
"And they don't have a 401k? What kind of revolution is that?"
He stormed off and someone said I was judgemental. Okay.

A very young man asked me for money and I suggested he get a job. He laughed and said he didn't want to work. I said I didn't want to give him money. As he left, two people I was sitting with said I was judgemental. So, I called to the young man, "Hey, these people want to give you money." Of course, the two people started telling me to shut up.

I was chatting with a man I know and another man, apparently a friend of the other man, sat down. He started complaining about laws that prohibit a mature man from having sex with a young man. I asked what laws he was talking about and when he told me I said, "Those laws aren't about young men. They're children. And, you're not mature. You're past your shelf life you frigging pedophile."

Later, the man I was talking to said I was judgemental. I agreed and suggested he try it sometime.

Why is judgemental bad?

Judgmental means either:
(a) using judgment
(b) being critical, or
(c) trying to influence opinion by using loaded words

(a) and (b) seem fine to me, though people don't often like to be criticized. I'd say that this is where there problem is - people think that you are unfairly criticizing them. You don't really spell out the context, but as long as you were polite but logical (as you were in the first two examples) they are just being a little childish. Of course, it might be that they feel you should have understood their position more before you judged them, but whatever.