Not sure why this is so mind-blowing; it's no different than any other option.
You don't have to own gold in order to buy a put option that would pay off when the gold price crashes.
There are some unique things about CDS -- namely a lack of transparency that's outsize to the notional value of the contracts, combined with an interesting twist on bankrupcy preference -- but this "nakedness" is in no way unique to that market.
The real issue with CDS has been the propensity of *sellers* to misjudge the liklihood of default, or rather the correlation risk of their entire book defaulting at once, leading to unbounded losses.
*Buying* CDS is just garden variety betting-on-an-uncertain-future speculation.
/jordan