There are some statements about the parking fee that are not correct. Any company that has a transportation concession with Disney does NOT pay the taxi/limo/shuttle/bus fee. For example, Checker has the taxi concession with Disney so they do NOT have to pay the fee. City Cab and Yellow Cab, also owned by Mears, do not have the Disney taxi concession and would be required to pay if they were dropping off guests at a theme park. If the passengers in a City Cab or Yellow Cab were guests staying on Disney property, they would not be charged the fee. On the other hand, passengers in Yellow or City cabs who were not staying on Disney property would be charged the fee the first time the taxi passed through the gates.
Disney Magical Express buses, owned and operated by Mears, do not pay a fee. Mears Motor Shuttle would not pay a fee, if they had the shuttle concession with Disney. It's been a while since I checked, so I don't know if they are still the official shuttle company. When I drove a towncar for Mears, Transtar had the towncar concession, so we had to pay whenever we dropped off a guest at a theme park. It sucked, but there was nothing we could do about it. It didn't happen too often, but when it did I just ate the parking fee.
The gate in front of the Magic Kingdom is a non-issue, if you know how to use Google Maps. The only gates you have to worry about are EPCOT, DHS and AK.
Some cast members are nice and they will let you drop off without paying. Others are Nazis, and they seem to enjoy collecting the money.