Oh wow, reading more into it, some credit cards are actually unsecured (but some aren't [0]). However, credit card companies can still sue you even if it is an unsecured loan and then repossess some of your stuff depending on the state [1].

[0]: https://www.nerdwallet.com/blog/credit-cards/credit-card-bil...

[1]: http://www.natlbankruptcy.com/credit-card-lawsuits/