Feet do show up on signs, but always in large round multiples of 100 feet. They tend to only show up on low-speed roads though -- signs like 'blind driveway 500

Feet do show up on signs, but always in large round multiples of 100 feet. They tend to only show up on low-speed roads though -- signs like 'blind driveway 500ft'. On highways, distance signage is almost exclusively in miles and fractions thereof.