[@Ebonsquire] Because it's really fun to picture characters together for any variety of reasons, be it the on screen chemistry or because they work so much better than the 'canon' pairing or something else. But shipping can also be a dangerous path to walk because some people take a sick sort of joy in making sure your ship crashes and burns and god dammit Jason Rothenberg why would you do that you asshole. 


It's mostly just a fun thing to do for a lot of people.