Any shop that passes a car w/o cats and doesn’t know the owner is nuts. The state sends setup cars out there just to catch bad shops. The fines can be sizable and a license suspension can be costly business-wise.
Hell, I remember we got fined because one of our guys had tinted windows. They noted his sticker and the tint, then when they came back for the routine occasional visit later, they saw the new sticker, knew by the numbers it was our and that was it. We caught a setup car once for no cat. But the damn things passed emissions. We got lucky on that one that we saw no cat. Back then, the DMV guys were very adversarial with shops, like they hated the shops. It was rather unfriendly. They would yell at us for not initially failing a car for bad tires when they saw new tires on the invoice. I guess their assumption was every tire that was replaced would fail inspection.
I hated those ****s. We ended up billing some inspections on their own invoices, separate from the work. Because we didn’t want trouble because some guy bought wheel & tires the same day he got inspected.
Then again, unless your car is crazy fast (say sub 12), modern cats are not that big a liability like the old days.