The struggles of the poor ("poor" as defined by the original post) are not the same as the struggles of a fresh college grad.

Households on minimum wage are often paycheck to paycheck, and thus have no buffer with which to even find a roof in a new city, much less hunt for a job in a less-reliable industry.

Also, familial connections are not just purely for joy - they may provide some amount of free childcare that would become a financial burden after moving away.