I agree. People tend to get too concerned that someone is going to steal their ideas, but the truth is that you can knock yourself out trying to keep a monopoly on an idea that someone else in all probability might come up with independently anyway. Better to use that energy on what you're actually trying to accomplish, and submit yourself completely to the body intellect for maximum assistance. Everyone has a unique slant and motivation for what they do, so as long as you keep your ambition cranked to get something done there will be inherent value in your accomplishment regardless of its similarities to those of other people.
That said, there is another factor on this that I'm sorry to admit I've fallen victim to myself on occassion. I'm talking about being ashamed of your idea because you haven't been able to completely think it through by yourself, and you become too self-conscious out of fear you will be socially ostracized for the weirdness of your idea. Every new idea, or new slant on an old idea, needs to be coaxed into meshing with all the other ideas out there. I guess what I'm trying to say is that badgering people, or rather, coercing them, to share their ideas and the fruits of their/our labour more completely is not going to entice the desired result. I think you're right to expect that we should ask.
So come on... don't be afraid... share your idea... come on. Dammiit COME ON! Okay, okay, when you're good and ready...