The issue is weight - state highways are frequently used for landings in Alaska. That doesn't mean they're good to go for a 737.
The actual "failure" loads are orders (yes, plural) of magnitude higher and most failures aren't the kind of catastrophic thing that people on the internet typically try and imply unless you get really unlucky and your mountainside shelf road turns into a landslide. Failure usually means you park a heavy object somewhere and come back hours/days/weeks/months later and find that it sank or slid slowly downhill in that time.
Short of maybe, maybe, landing a fully laden C5 on everglade highway or redefining landing to include crashes where the tires happen to be the first bit to crash you are going to have a hell of a time displacing the road bed a meaningful amount with an aircraft without destroying the aircraft. They are simply not strong. They have to be light enough to fly you know.
Never-mind the fact that they used to fly these things off of dirt strips...
At best you might displace the asphalt a little and leave some ruts behind you. Remember, these are vehicles on pneumatic tires. Their point loads aren't high enough to really cut through pavement. All you can do it smoosh it out of the way. And the road bend was made of gravel of particular size and roughness and then gone over with compacting equipment to prevent exactly that from happening, albeit over time.