I think this is one of the beautiful things about the boating community. Most of us have needed to be helped at some point. So, most of us are ready (even watchful) for someone who might need help.
On my local lake, our boaters club works in concert with the sheriff's office/911. Most calls from boaters are not life-threatening. They are just folks who need some assistance (usually a tow). We can respond much faster than the sheriff.