I see what you mean on your screenprints.
I don't see any ad when I look at the page myself. I'm a regular visitor here, as you can imagine, so I invested some time in blocking scripts and ads on CNET pages to get pages showing faster. That seems to work quite effectively.
Also, but that's a little bit off-topic, I prefer to download from the makers own site (or sourceforge) if possible. That's always one of top hits in a google search for DOWNLOAD XXXX (with xxx the program name). For Avast it's http://www.avast.com/free-antivirus-download and the top link indeed. This, by the way, is more or less a necessity, as that ad blocking I mentioned blocks dw.cbsi.com (where those downloads are coming from) also.
I fully agree that it's misleading. If you know it, it's rather clear that that two download buttons at the top and at the right are for ARO 2012 and Regclean Pro, not for Avast. But I can imagine you don't notice it if you don't know it.
Let me stress that ALL mods and most regular visitors here would tell you to stay away from both products. We don't believe in system optimizers and registry cleaners and we advice to NOT use them, and we really strongly advice to never pay for such products. Just read the reviews for ARO 2012 in http://download.cnet.com/ARO-2012/3640-2086_4-10183947-1.html and you'll understand.
But, alas, our sales department only smells the money.
I'll alert your post to our forum manager. He might be able to convince the sales people that ads (for any software, not only these scams) with green 'download now' buttons simply shouldn't be allowed on our download pages with our own green 'download now' button for the software our members search for.