If flip-flops were added to the game, would there be unique sound effects for footstep audio compared to shoes and space boots?

Absolutely. It's not a trivial thing. Francesco, one of our sound designers, is really fleshing out the Foley system at the moment, and he's looking into increasing fidelity in regards to character loadout and footwear. So if flip-flops came in, we'd absolutely have to record. We don't have any, but we'd definitely record some. There's a film, The Social Network, the social media giant film that came out. One of their funny considerations was making sure they got loads of flip-flop stuff, because the main character in the film wore flip-flops all the time.