And why the heck does possess have to have all these esses?

Because it's like that, and that's the way it is.

How riveting. Are you always this interesting? I wish to subscribe to your newsletter. 

We can dispense with the first set of two s's, I should think. Double "s" usually signifies an unvoiced /s/ anyway, not a /z/ sound, as it is in "possess". The word sucks 

My answers like this are more rivetting and interesting than those of anybody who does nothing but criticise the English language. At least I don't do that. Lol:)

Well, if you cut it back to a reasonable number you have "posse", ... and that could lead to some problems.