Placing this here because I don't see any other discussion on Road Type, and it really boils down to Parking Lots anyway in this case.
I made the following addendum to the USA Road Types
Note: There is always an exception to every rule. If in doubt, consult with a Waze Champ or Country Manager (Indicated by Level 6 next to their name in the editor) before making exceptions.
The bolded part is what I added. After pasting the URL to this page into a PM for the 100th time, I noticed that the "exception to every rule" leaves everything on the page open to interpretation, so I felt it was best to put the disclaimer in. This will reduce the likelihood of new users openly interpreting the rules and getting themselves into trouble, and increase the likelihood that they'll contact a senior editor and get the proper direction they need.