Originally Posted by perttime

Folding wings are handy for storage. A hook and sturdy landing gear are handy for using short and rough runways, such as straight pieces of road. Finland still stays prepared to use roads for air bases, as there is no realistic way to keep a "major enemy" from breaking the peace time air bases.

http://www.youtube.com/watch?v=XNtFc0Z44m8

They don't use the hook routinely but practice its use at land bases.