Why use Twitpic or Instagram instead of Twitters photo integration service?

[vampiresa]

I am new to Twitter, so I am trying to understand why people dont just upload photos using just Twitter.

Apart from the fact that you can use filters in Instagram, why use another site?

[Hadi]

Mainly because human beings are stupid.
Our poppulation is gradually being brainwashed into becoming stupider and stupider. You might think :"Well wth does it have to do with this?" Well it's because some of our fellow human beings can't tell that a filter wasn't invented when Instagram came out, and that they have been around for 20+years. We also like any place that has #Swag posted anywhere on it.
We also seem to like post pictures of food.