You just reminded me, there were other checkpoints to. There was the agriculture check point going into and out of California/Arizona border. We got stopped we were asked if we were carrying any farm produce then sent on our way.
There was an informal one on I-15 going north. Had to travel that frequently when doing work at Ft. Irwin. BP would slow you down, and in my case where driving a rental T-bird or whatever, bounce the trunk to check for the weight of stashed Mexicans, and that was it. No lined up mile of cars like at Camp Pendleton.
I told them at the Oregon border that I probably had Oregon lettuce in my teeth. Then I told them if they were really serious, they would make everyone take a laxative at the border, then have someone make sure they cleansed befor crossing.
He didn’t get my Georgia humor and sarcasm.