Is CBP Actually Fining $5000 for SENTRI Lane Violations?

In 24 hours last week, I was contacted by two separate individuals who were fined $5,000 by CBP for SENTRI lane violations.  If this is a new policy, a $5,000 fine seems like way too severe a penalty imposed by CBP.   Both individuals appeared to have similar fact patterns.  Neither party had a SENTRI pass.