That makes sense; if a character is fat enough to need a care home, they are probably past the point of using mobility scooters to travel into town.
Overriding the player's decision at barely mobile could provide another advantage to owning a scooter or high fitness, as both of these could allow the player to overcome it. I'd like to introduce player Dizzy's addiction, which might work similarly - the player would have to pass a roll check to see if they can do what they want to do.