That’s a little bit of a harsh interpretation of the parent comment. I think it was a valid point... if you’re looking for some peace and quiet and stunning surroundings at a reasonable cost, there are tons of fantastic backpacking options. Not having any religious/new age affiliations is (for me) another bonus of the park system.
Applying some common sense, they probably mean 'for off-the-grid austerity [in commercial retreat accommodation available in the US]'.