i just had to add this post. what you're saying is true of every red dot
EXCEPT the aimpoint brand. they are completely parralax free. that means you don't have to center the dot in the reticle to hit your mark. one of the reasons, i guess, they are pretty much becoming standard issue to SWAT teams and military personnel around the world. check out their website.
www.aimpoint.com . it's pretty cool.