I think a surpising number of people in coastal areas have PFDs in their cars, not the majority by any means, but most of my friends from home do because they/we boat so often. Have to have the life jacket for the Wednesday night it blows (we race sailboats on Wednesdays)!

The boats always have the sort of basic orange PFDs, but we usually bring our own more comfortable type.

Re raft in the attic - While I wouldn't knock someone for going this route, I'd rather just prep a boat pre flooding conditions. I couldn't afford a quality raft for the attic and I'd rather have the boat than a mediocre raft.

How would I prep the boat you might ask? It depends entirely on what sort of flooding I expect. A hurricane is the most likely cause where I live, so I'd tie several boats of various size down at elevations unlikely to flood, then post windy event, if for some reason (A medical emergency is all I can think of) I needed to go out into the flood waters, they'd be handy.