That is why I download avast on filehippo instead of cnet. I just the articles posted on cnet but I do not download any software from there.
+1 cnet.com has their own downloader which to me is too intrusive.
I now use filehippo.com or softpedia.com 
I think I seen them offer something like that before, but I never even get asked anymore. And ofcourse if I were to, I/You just say no. And it's really that simple. Just like installing say Firefox and they ask if you want the google toolbar and such...