But creepers only explode as a consequence of interacting with you, if you keep your distance then they can't interfere with the landscape or your creations. Endermen mess with blocks even when you're nowhere near them. If a creeper blows up part of my wall then I can accept that because it's partially my fault. If Endermen could only move blocks after you've "triggered" them then that would be much better.
Yeah, exactly. It's in the long-term that endermen are more destructive. They take away blocks even when you're not there, whereas Creepers only get triggered into their effect when you're near them, making them exactly like griefers. I think Notch meant it for it to be a playful idea, but didn't realize the kind of damage they could do if left to their own devices. It's said that the endermen we got are very different than what was first proposed, as originally they couldn't touch player-placed blocks, and seeing that they're buggy, I wonder if it's because some of the things about them weren't fully implemented.