Likely against regulations, but ...
you could BIVOUAC,
if you are alone or with just one other person,
do it off the trail,
right before or after dark,
pack up first thing in the morning,
and leave no trace.
If you want to CAMP, or are with a large group, do so in the huts or in the valley campgrounds.
In Switzerland (Interlaken), I remember an official looking helicopter came snooping around the area right around dusk.