Dean could get a job—a legitimate if not actually legal job—at any garage in the country, just by showing off the '67 Chevy that's been driven a million miles and been rebuilt once from scratch and probably a cumulative five or six times over its lifetime (no one cell in the human body is more than seven years old) and is running better than new. Sam's vastly overqualified for any under-the-table job he could get, but he's six-four, muscular, Marine-trained, and he's got experience as a bouncer (kept him in beer and pizza through college, and ammo for a while afterwards, since he wasn't buying any engagement rings); he'd have no trouble finding employment.
Sneaking merchandise past security, hustling pool and poker, and thinking up names for the credit card applications are all emmuch/em more fun.