Hmmmm ....
First off, you sound a bit "rambunctuous." (however one would correctly spell that word - especially this late
)
Everywhere I've lived, if an LEO asked me these questions, I'd say, "Yup, a key in the back, but Dude .... " & we'll just split the profits - likely he'll help with the distribution. Hey! I wuz gonna sell it anyway ....
Sure, the cops'll ask you The Questions - never known it TO BE DEPARTMENTAL POLICY, per se, but so what?
Tell 'em if you have firearms (if you feel like it) & too, that you do not give permission to search (that 4th Amendment thing).
Frankly, what you have in your car is none of their business.
They wanna go fishing? Make 'em get a warrant.
Still, Sounds like you had a "bad stop" & are venting a bit. We need more info to walk this one through.
Care to share?