I've just never seen them listed like that; whenever I've looked they are either not there at all, or they are the sort of reservation where you pay hotels.com up front. And I've seen the onsite resorts listed with ALL the info you need before, too. So I was definitely confused, and was glad I checked really quick using my phone.
The site I love to use is
this. It's the official Loews booking site; it's just different than going to universal's site or loews' normal site because it shows all resorts at once.
And you can check, through that site, on each hotel and what they have. From RPR's page: "Self parking fees are $18 per night and valet is $25(per night." There is tax added to that, by the way. But they charge at midnight, so on that last day you won't have an additional parking charge unless your car is still there at midnight AFTER checkout. Assuming you have a car.
I have not encountered additional fees, and I've now stayed at all three onsite resorts. (next year there will be 4 but that's not yet) You get the unlimited Express Pass from the moment you do the checkin process (including going to the kiosk in the lobby and taking a picture for the express pass), you can charge back to the room, have purchases sent directly to your room (unlike Disney's not quite similar service)... They encourage pool-hopping; just bring your keycard. And apart from parking I've never had a fee.
I did notice that hotels.com is charging a little fee, which is pretty weird IMO. Then again, if you book through Loews, you'll pay one night's rate (plus tax) as a deposit. The rest is due during your stay.
I hope that helps.