Not sure about breaking into cars specifically but the recent popular video where the former NASA engineer designed a device to film people stealing packages off of doorsteps seems to both confirm your statement about not being downtrodden but dispute the idea that thieves are homeless or junkies. Almost all of the people that he caught on film stealing in that video were normal looking middle class people that had cars, apartments, houses and didn’t seem to have any mental illness other than a complete lack of empathy for others.