Sockets, yes (often more than one, in fact). Lighters themselves, probably not.

The socket has evolved well beyond its initial use heating up a cigarette lighter.

I use my 12v socket to power my portable air compressor.

Probably? I confess I don’t know. Car accessories that use them are pretty common tho, so probably.

Most do. But it might just be USB sockets around the dash area or center console. Still probably at least one 12 V one somewhere and often one in the trunk.