Actually here it is quite common. I'm in AK and we have 3 coast guard installations in town. It's not uncommon to see them moving the 25 ft Defenders between sector Juneau and Auke Bay or Mayflower Island on Douglas. They can't go up the channel due to the water getting to shallow near the airport and it's quick to pull them over land then take them around Douglas Island and back in to Auke Bay.
On a side note, just donated and can't wait to play with this mod.
I get to work with the coasties a lot during the summer doing open water medevacs from cruise ships and them pulling people out of the water. Actually had to work a code in the belly of one of there 45 ft Medium Response Boats.
Also a suggestion, if I may, for at sea medevacs, like I've seen in Acepilot2k7's videos, have a city or private Ambulance meet the boat at the station if you choose to use a boat. Most of the Coasties have basic first aid, some may have EMR, but unless you are a corp man or rescue swimmer you don't have the advanced EMS training, hence why I have been on the coast guard ships a few times a summer.