Seems to me that deputizing a CBP agent and allowing them to issue traffic citations could lead to a waste of resources.

If a CBP agent issues me a traffic citation and I decide to go to court to fight it, does the federal taxpayer really have to pony up to pay for the CBP officer sitting around in court? Or does CBP then seek reimbursement from local LE?

In spite of what some say, if a CBP officer at one of these checkpoints decides to interrogate the occupants of an automobile, demand to see ID, demand to search the vehicle, it is a brave citizen indeed who will risk saying 'no'. An honest agent without a chip on his/her shoulder may allow it, but it is equally likely that the agent will turn the encounter into a p*ssing match, and everything is in his favor.

Unfortunately, it is equally questionable whether or not more professional agents and supervisors on duty will call 'foul' or just back the agent up.

Functionally, you have no 'rights' in any encounter with CBP. Anyone believing otherwise and attempting to exercise their 'rights' is taking a big risk, IMHO. Much better to practice humility, obsequiousness, 'yessir'/'yes maam' everything, copious butt-kissing all around.