"I'm not harming anyone!"

That isn't true, though. Harm isn't just physically attacking somebody. Using/taking what is theirs, without permission, is a form of harm. You won't want someone taking your stuff, but you're taking someone else's, and that's wrong.

Honestly, I expected better of you. This could have been a great discussion about how to ethically camp stealthily. Like you said, sometimes it's necessary, even if you're not doing anything wrong. Instead, you used it as a chance to advocate for theft, and speak out against private property rights.

I guess if you're living off other people's land (and resources on their land), your opinion would be "I'm doing nothing wrong". Your justification is weak at best, though, and the logic of your viewpoint is nonexistent.