There is a great blog post by Todd Litman on Planetizen about why car dependency is a major factor in fueling poverty:
Entertainer Will Rogers once noted that, “The United States is the only country ever to go to the poorhouse in an automobile.” This has become tragically true for many low- and moderate-income families.
For example, thousands of automobiles regularly line up to receive food bank packages, as illustrated in the photo above.
These are mostly nice SUVs, light trucks and vans, the types of vehicles owned by responsible families living in automobile-dependent communities. Automobile food bank lines are, to a large degree, a self-fulfilling prophesy: Because residents must drive everywhere, they have high transportation costs, leaving inadequate money for other essentials like food, shelter and healthcare, which forces them to depend on charity.
He writes a convincing argument, and I recommend reading the whole article. One of our biggest collective mistakes has been making car ownership the entry-fee for participating in society.