You shouldn't abuse your work privileges.
Artie has access to a company car at his job and has the weekend off from work.
Artie wants to go out with friends for the weekend.
Artie uses his own vehicle for the weekend because he likes to keep the company car in pristine condition.
Artie uses the company car for his personal travels over the weekend, so he can take advantage of the free gas.
Artie's boss always appreciates the condition the company car is in and never has to worry about it.
Artie's boss is annoyed that Artie used the company car outside of work and has to think of a punishment.