The 'car bit' is relevant. Very relevant. There will be many, not all but many, inexperienced hirers who will have been told 'it's just like a car' or words to that effect.
Well, I've not yet driven a car in well over 50 years that steers at the back wheels. Also cars have effective brakes ! These essential differences should be pointed out.
There are more than a few boatyard staff involved in handovers who are very well experienced in handling the boats in their fleet and appear to 'show off' with high speed manoevers . Is it any wonder that the first time boater senses (wrongly) thats the way it should be done ?