I run a restaurant in California and every multi-use item touched by a customer in any way gets washed and sanitized, even if we use wax/paper wrappers.
The actual law is in Chapter 5 of the Cal Code (for California, obviously): http://www.cdph.ca.gov/services/Documents/fdbRFC.pdf
No idea if there's noncompliance rates out there though. (I also don't want to think about that, ewwwww. I hope that means that the restaurant's permits get suspended.)
The actual relevant quote is from Chapter 5:
114097 . Equipment food-contact surfaces and multiservice utensils shall be effectively washed to remove or completely loosen soils by
the use of manual or mechanical methods necessary, such as the
application of detergents containing wetting agents and emulsifiers,
acid, alkaline, or abrasive cleaners, hot water, brushes, scouring
pads, high pressure sprays, or ultrasonic devices.