heh... that's quite an interesting theory! But it's really just that, a theory.
I wonder what you had in mind with that exhaust?! But actually, these rolling shutters are designed with slots to let airflow through when they're not rolled down all the way... sooo, yeah, no real need for an extra exhaust here.
source: product website
A little periscope would be funny, but I guess one can also just peak through those same air-slots instead.
I can assure you though, there's no malice involved, it's of purely practical purpose!
There are no nice puns about buffer stops for roller shutters aka Rolladen Anschlagstopper. They are used so that the shutter box does not eat the whole shutter D:
Imagine your nose was used as a buffer stop... ouch!
Roland rolls his new eyes, but he's still a blind
I shutter in fear at the thought of that