You can see them from any of the MK hotels, the better ones are the beach at the Poly, the deck at the Contemp, the docks at the GF.
Not sure about WL since that has some pretty tall trees there, but a WL expert should be able to give you a location.
As far as the docks or beaches being only for the respective hotel guest, well we're not and plan on watching the private press party ones on the 8th from the Poly. We leave the 9th and will miss them by 24 hours. We are staying at the AKL and there is NO WHERE that states these are areas for hotel guests only, at least that I've seen. CMs have pointed me to these places. Sure the pools are one thing, but a dock, come on that's just goofy.
If a CM was to ask me to leave and tell my it was for Poly or GF or ??? guests only I would, but I've never been asked to leave and never has a another guest said anything to our party. I think some people are just too darn uptight. LOL I guess I could say the same thing to them, you can't view the animals at the AKL because you're not staying there. That sure would go over well. LOL
I say if you get a chance and want to see them ask a CM at the hotel for a good spot and I'm sure they will point you in the right direction!! This has been the case for us for several trips! And the EWP is a huge bonus, small but really neat to see!!
Pam