I really wonder why people prefer some other websites to download the product instead of its own website. When you type "ccleaner", "kmplayer" etc on google, the first one is always the product website. The second and third ones are the websites distributing product with adware/spywares.
Maybe they're looking for a trusted curator or the "user" reviews give them a sense of reassurance. As an exercise, try to find the right download button on Imgburn's own website:
I installed imgburn, I was careful to uncheck everything, yet I still ended up with OpenCandy. I -probably- fucked up, but I don't see why someone who is shady enough to bundle OpenCandy wouldn't also be shady enough to ignore what people choose during installation as they will usually only blame themselves.
Anyone can do that, even people that know where they should type the URL! Do you always carefully check that the right box has the keyboard focus before you start typing?
It's not a "can do that" issue, it's that they always do it. I have multiple family members who Google (or Bing...) "Facebook.com login" every time they want to use Facebook...