No, I really don't get it. It is disappointing when people don't share, or don't reply to messages, but I really don't mind people copying chunks of my tree. It's no skin off my nose as they haven't deprived me of anything.
I have still had the great pleasure of doing the research, which I don't regard as "hard slog". Yes, there has been some expense, but that's offset by the anticipation and excitement of discoveries. None of this has been taken away from me, but someone who just copies large portions of family trees has missed out on all of that.
What does upset me a bit is that I can't interest my family on one part of our tree. There are only three of us descended from this branch, but they just aren't into it, so I have no one to share this part of the journey with. I so wish I had started it a few years earlier when our parents were alive.