I'm not the guy from above, but responding with "I disagree with you so are you sure your opinions are your own" is dismissive and doesn't lead to a more interesting or thoughtful discussion. Instead, asking WHY he believes gives you the opportunity to engage in the discussion, maybe change your views a little or change the other persons' a bit.

That's why comments like that are annoying, they're a way to dismiss discussion instead of engaging in it, and engaging in discussion is the point of this silly site.

I'm someone who also isn't wealthy and disagrees with wealth taxes. Responses like that one aren't an honest attempt to engage, and I'd also ignore it and move on :)