Taking someone else's belongings is not okay.
Joe usually rides the bus to work while his roommate Frank drives to his own job at the same time.
Joe wants to get to work.
Joe walks to the bus stop and takes his regular bus to work.
Joe takes Frank's car without asking and drives to work.
Frank drives his car to work on time and earns his pay for the day.
Frank doesn't have a way to get to work, misses his shift, and doesn't get paid for the day.