Prepaid debits for online transactions: they provide fraud and theft protection. Credit cards only if a transaction specifically requires it (usually rentals) or if an extended warranty is needed. Cash for everything else, especially convos and gas.
I think it’s much more likely they recover the stored info the same way: 1-2 weeks later, one member causing a distraction, while the other member removes the now-full skimmer.
I doubt there’s a standards association for POS skimmers, or a Skimway multi-level marketing selling devices, so it’s probably a lot of everything — whatever works at least once.
Still, scanning for strange devices might not be a bad idea, but be careful what you connect with. (And always know where you are.)