When the family gets too drunk to drive home at the Langley Falls Oktoberfest in "The Fast and the Spurious", they call for Klaus to come give them a ride home rather than trust Roger's bad driving, despite the latter's staying sober during the event. Steve doesn't have a license, Jeff is unable to drive after crushing his legs in a beer stein race, Stan describes himself as wasted andFrancine as hammered. He simply knows Hayley is drunk because he likes her as a person when she's like that.