Why are nonprofit meetings at the most inconvenient times?

I have one really big annoyance when it comes to nonprofits and community work.
All meetings seem to happen at the most inconvenient times. They expect community leaders to come together usually for times more than an hour, not including commute time, and usually schedule the meetings around mid-morning, or mid-afternoon.
And that really annoys the hell out of me.
Why? Because I like to stay involved. No, I don’t like to go to meetings that don’t accomplish anything. In fact, if you have me go to one, and it doesn’t accomplish anything, I refuse to go to another. There’s precious time in the day for this guy, and I got a lot better things to do. But in reality, my job, and I’d imagine that most jobs don’t let you just prance out whenever to “take a meeting”.
Who the heck has time to take off between nine and eleven? That’s the entire morning. So basically, community efforts force me to take vacation for half the day. And that just sucks. Believe you me, if it goes nowhere, they’ll regret losing this outside-the-box thinker.