"All but a few range from neglected to abandoned in appearance on sat views."
There's several them actively used by the tourism industry, I've been to 2 myself, and know of at least 2 or 3 other ones that are actively used.
Cuba has an active Mig-29 squadron I believe, not sure where they're based though ... Last time I flew into Holguin, that airport was shared with military installations ... heard a few helicopters flying around but that was it ... there were some older migs on the ramp, though they didn't look like they moved too often ...
So there are people that fly there ... does that mean they have 100LL, or you just make sure you fill your tanks to the brim and plan the return trip accordingly?