Camping reservations are hard to plan for on a tour when you don't know how far you'll be going and things don't go as planned. Bike travelers with no motorized support can be stranded if they are turned away from full campgrounds and other accommodations are far away.
A no-turn-away policy or directive is one way campgrounds can guarantee an emergency camping space for small groups of self-contained bicycle travelers who arrive at a full campground.
(see also Camping Rules & Regulations)
(see Bicycle Tourist Camping)
Photo courtesy of Oregon Parks and Recreation Department