First, according to maritime law it's your responsibility to assist when a mayday is called.
second, the sea is one of the few places where there's still some sort of non-monetary, honour-based system where people will help each other if needed. I've personally helped folks in trouble with risk to my own boat, and I'd expect someone else to do the same if I was in a tight spot. It probably has to do with the environment - the sea is very lonely. If you are having an emergency there will be no police, ambulance or firetruck coming. You have to fix it yourself. If you're lucky another ship is close by.
second, the sea is one of the few places where there's still some sort of non-monetary, honour-based system where people will help each other if needed. I've personally helped folks in trouble with risk to my own boat, and I'd expect someone else to do the same if I was in a tight spot. It probably has to do with the environment - the sea is very lonely. If you are having an emergency there will be no police, ambulance or firetruck coming. You have to fix it yourself. If you're lucky another ship is close by.