Most users are just consumers and are not interested at all in Nmap. CNet have been doing this for at least a month maybe two.
I downloaded a simple utility.... I'm too simple to remember what it was... from CNet around six weeks ago. The installer by default would have installed some toolbar until I cancelled the install.
It's not just Nmap. I think CNet want to, or are in the process of, lacing all their downloads with poison.
We are IT professionals... At least I think some of us might be, and we find it easy to see when something isn't quite right. Your average user on the other hand is just a consumer with little clue about such things. What's more they are more inclined to leave tick boxes ticked when they have the word "recommended" next to them. I know this for a fact and you would too if you ever cleaned the crud from the machine of an average user.