As a test, I recently started writing replies to emails from some big name marketers whose lists I'm on. I just wanted to see if they actually paid any attention or if their list was all a one-way street. I wanted to see if I was just a "buy or shut up" non-entity to them, or if any of them actually cared enough to reply to one of their subscribers who had a question.
Zero. Zilch. Nada. Crickets chirping were heard for miles around.
Not one of them "bothered" to get back to me. They don't care. You're just a dollar sign or a nuisance to them. Not ALL of them, of course, but a lot of them (sadly).
Don't be that guy or gal. Please don't. So much of your success if you're selling in the IM niche is determined by your accessibility and your "real human" qualities. It's just foolish to ignore the people who sign up to your list. That's your bread and butter! Treat them right.