I know for Mt Hood -
They do have GPS rentals available for the hikers/climbers - only 5 dollars to rent I believe.
They probably should give them out free so climbers will use it & it would save time & resources when a rescue is needed.
Then they just turn them back in after the climb.

But some don't want to use that extra bit of security
Or they don't think they will need it...until it's too late.

In 2002 a chopper crashed on Mt Hood while trying to help with a rescue.
http://archives.cnn.com/2002/US/05/3...hood.accident/