in a major beach environment like that where you have tens of thousands of people on a beach daily for a long season it certainly could be offset by a beach charge , buck a person a day to support every day lifeguards are on the beach , no life guards no beach fee.
or like most ambulances they bill the person recovered as collecting a fee would incur cost to collect it.
it was 250-400 just to sign the form saying you didn't need to be transported to the hospital and it was like 1200-1500+ for a person transported to the ER depending on what needed to be done to stabilize or on the way.
what you are really offsetting with this is personnel costs , this is often the real issue
they had atvs , they even have atv trailers that can launch rescue water craft with the sled on the back they could run watercraft up on the beach then grab the sled and pull then farther up and transfer the person to a truck or utv to be taken to the ambulance in the parking area.
but that takes people at every step this may not even cut more than a couple minutes out but it cuts several people and other pieces of equipment out
if you can be patrolling with 1 of these and 1 standard quad and see a rescue need those 2 lifeguards can get to waters edge the second quad driver jumps off his/her quad and gets on the sled as the rescue diver they cruise out to the victim and then can run all the way up to the parking area and meet the ambulance
med supplies can be stored on the dry quad so that if needed they can work on the person at the shore before further transport
speeding up the rescue with half or less the people
making it possible for fewer people to patrol and perform rescues in less total time as there is no reset getting the watercraft back on the trailer