its cause 4chan isn't one united site.I really Dont get 4chan. One time they are pro loli other time they re anti loli.
The boards have different users, and the users fight (or at least used to) each other a lot.
Ancient history, but the whole Tumblr Wars thing was /b/ fucking with /pol/ no?
anyway, point is they aren't all the same. Different board, different opinions.