Stretch your legs and get cultuREAL heritage?  Sure would beat all the
vending machines in and around the bathrooms!
 
Also, Why not put some of the roadsigns themselves into the roadside
display as a testimony to a time when the belief in observing them was
much more common than it seems to be today.
 
We could include psycholinguistic history for words such as "roadkill"
and "speedzone," or devote space to post accident - pre-wrecking yard
vehicles to document the "actual" activities of roadside users/dwellers.
 
"Through No Asphalt of Ours" could be the exhibition title, with exhibits
north and south along I-5 on the West Coast...could be a moving
exhibition, so to speak as well...visiting perhaps your states' freeways.
 
And What about Mall museums, Supermarket museums, and fast food joint
museums?  There are more opportunities than money, but hey!