I have anecdotal evidence of this from the recent housing bust. One friend who's worth several million walked away from a $700k mortgage when he realized how upside down it was. Another friend who's worth less than $100k stuck with a $300k loan and even doubled down, sunk in her entire life savings to refinance and reduce the ballooning payments. Despite my pleading her reasoning was a moralistic attitude of "I gave my word". The friend that walked away recently bought a new house and is doing better than ever financially while my other friend will be feeling the pain for years.