[Bolo4u]

Generally speaking, at the AG inspections stations located at the border crossings into California you are required to stop. They are inspecting for insects which can be harmful to Californias ag industry. Also, they will inspect boats and other water vessels coming in from out of state which may be carrying invasive water species (zebra mussels) etc. and some regular vehicles from states known to possibly carry insects or other harmful organisms. If you're coming back to or traveling to California to camp and you have firewood you bought at the local out of state KOA or firewood you brought from home they want to know. Also, if you've been out of state hunting, you're ~supposed~ to stop and declare your tagged animal. So far, California has avoided Chronic Wasting Disease and if any deer/elk coming from out of state still has any brain or spinal tissue intact... bad juju. If they catch you you might be caping the animal on the spot, even if its 2 am. Yes Ca Fish and Game will stage several officers at Ag stations, especially during heavy hunting seasons.

They aren't looking for the groceries you just purchased at Costco. More the box of strawberries or other fruits/veggies from the local farm stand 40 miles back.

As far as the weigh stations, if you're driving for-hire (commercially) you're generally required to stop. If you're from a state that issues separate weight stickers (the CVRA stickers in California) then technically you're required to stop. Rv's are generally exempt. Moving trucks are not...