Yes and it's not nice to give people problems. It can even come back to you if they don't feel like they got a clear response and continue to bother you.
I like to communicate in ways that are clear, honest and complete because that way people get the information they want and we can understand each other. I think the world would be a better place if everyone did that and therefore it's what I recommend people to do.
I agree and if I thought I got any value out of communicating extra to them I would. Fact is, this is open source, I'm doing this for fun. I'm not here for you and I don't owe you understanding or complete information.
The open source part of this doesn't matter. Open source means that the user has the right to use and modify and distribute the program; it has nothing to do with communication.
This is a communication question; it's about how to respond to people that are being annoying. It's always nice to do that in a way so that every one understands each other.
"Pull requests welcome" if you want the feature. "Fork off" if you don't.