If you're a Novice (not tech-savvy) you would actually believe them and download all the softwares from their database cause its freee,.. you're getting it for free. And if you're a tech-savvy or geek, you'd know in an instant that these sites offer what's called 'Bundled Softwares'. Yes these reputed sites have ties with third party companies which offer more than 2 or even 3 installation softwares with just one.
A best example would be 'Adobe Flash Player'. You go to get.adobe.com/flashplayer/ and you'll see 'McAfee Antivirus' downloaded by default. This is just to emphasize that a non-geek wouldn't know all these stuff and would simply click Download -> Accept-> next -> next -> Install.
Downloading bundled software decrease your PC performance and makes your pc more vulnerable to viruses, malwares. Some of these bundled softwares even contain fake applications. Yeah I tested it out on Virtual Box.
So my advice to you ? Don't believe in 'free' word on the Internet except for Linux & Linux related applications cause they really are.. 'Free as in Beer' reference. I'd suggest you download softwares from Torrentz.eu.