Tumblr Famous.?

I don't understand picture blogs like Tumblr. I think the purpose is to expose pictures that somehow relate to you and for people to pick up on the general message of what you are about. How is this true individual self expression, or unique for that matter. I like looking at cool pictures as much as the next person, but come on photo blog? You didn't even take the pictures you are posting. When people tell me to check out there Tumblr, I find it really strange. Beside the selfies that you have edited, I have no idea what message you are trying to send across. I don't know you. I'm a writer. I use my words. What are you?