The rules seem to suggest that a PCC is either being "carried" or "stored", both of which require an uncased PCC to be "reasonably vertical". This is the only thing I am aware of that may have gotten you the warnings. Personally as long as your PCC meets all the other safety requirements and it is placed close enough to the berm that no one would walk in front of the muzzle, I don't see the issue. But, I am not an RO; and I didn't stay in a Holiday Inn Express last night.
As far as penalty, I agree that it doesn't meet any of the 10.x rules. At most I would expect someone to just request that you put it back in the case.