You're walking home late at night from the bar because you've had 11 shots of tequila but you still made the conscious decision not to drive for the safety of others. You're crossing a stroad. Someone "in a hurry" decide to run the red light and hits you at 70 km/h (because of course they were speeding, why wouldn't they?), doesn't see you because you're hunched over while you're walking and it's really dark and the person is driving a giant SUV with shit visibility.
Cars are one of the largest source of fatal pedestrian accidents in a major city. How much more likely are you to get into an accident if you're drunk and is less able to pay attention to cars breaking the rules and putting you in danger? Walking safely in most cities is a task you need to be sober for because you have to walk super defensively.
It's also dangerous to walk outdoors at all. I saw the aftermath of a drunk driver killing a pedestrian at 6 AM a few days ago. There was debris spread for at least a hundred meters down the road. The news said the driver was uninjured.