A boardwalk in one state can feel almost interchangeable with one two thousand miles away. The similarity is not imitation so much as convergence on the same set of constraints.
The original problem was sand indoors
Early seaside resorts faced a practical nuisance: guests tracked sand into hotels, railcars and shops. An elevated timber walk let people move along the front without crossing loose sand.
That purpose dictates the form. The walk must be raised, continuous, wide enough for two-way strolling, and connected to the buildings behind rather than to the beach in front.
Once the shape existed and worked, later resorts copied it because it solved the same nuisance in the same way.
Building on sand forces a particular structure
Sand is a poor foundation for a slab, so the standard solution is piles driven to depth with a deck framed above them. The visible result is a raised timber platform with an open underside.
The open underside is functional. It allows storm water and blown sand to pass beneath rather than pile against a wall, and it lets sections be inspected and replaced individually.
Decking laid in short boards, whatever the material, exists so that damaged sections can be swapped without dismantling the structure.
Coastal rules shape what sits alongside it
Many states regulate construction seaward of a defined line tied to the dune system, and a walkway is generally treated differently from an enclosed building. That distinction pushes permanent structures landward.
The familiar arrangement of shops, arcades and food on the inland side with an open rail on the ocean side reflects that division. The specifics vary by state and change over time.
Storm damage resets them repeatedly
Boardwalks are periodically destroyed in sections by major storms and rebuilt, often to updated standards. Rebuilding tends to converge on current best practice rather than restoring local quirks.
Each rebuild also removes some of the accumulated eccentricity that made an individual walk distinctive, which flattens differences between towns over time.
Where the local character survives
Differences persist mostly in what happens on the boardwalk rather than in the structure: the games, the regional foods, the music, and the width and rhythm of the cross streets feeding it.
Older walks that escaped a full rebuild often keep unusual details such as varied board widths, original pavilions or an off-axis alignment following a former shoreline.
Those are the parts worth looking for, since the deck itself will look familiar wherever you are.