Because that's apparently too hard for some people.

Or, more accurately, they just want attention.

The Google machine is still a skill that a lot of people have not mastered. It's really sad. 

Shouldnt take skill to seach

"<name of image viewer>  <file format>" 

To find out if said image viewer supports said file format. 

I mean, these people have already asked the questions in their heads. they just don't figure that they could type that question into a search field and get an answer.