This is definitely happening. My colorado friends who leave the state are routinely searched in all the surrounding states for drugs. It's a common topic in chronic pain groups - how to drive with rx properly so you don't get in trouble.
One guy had a trailer and opened it for searching in three states on his way moving to florida. No one in his family does any drugs and he said it was very surreal. They need money and this is an easy way to get it.
OMG
I never even thought of that! I live in OR, also a legal state. Imma hafta remember that if I drive out of state...
Get the car detailed and carry nothing. Sad but true - also shield your cards from scanning. Have id for kids and all.