Had a similar inncident here.
A time my house was robbed the cops did a search through with my parents just to see what other damage there was. I was not at home at the time and no one was thinking so a cop goes right into my room, which at the time had a loaded with mag inserted G36 laying on the floor and a loaded with mag inserted Mac 11 on the table. Apparently the cop didn't even flinch and all that was said was "they are airsoft guns" and that was it. Didn't even pick them up to confirm.
It's shitty, but it's all luck with cops a lot of the time. They aren't robots. Most are humans and some are....just, dicks! Those would be the ones out on a power trip. Fortunatley I've found the vast majority of our police force to be very reasonable and understanding.