My initial thought is that that there are some fairly extensive parking lots (particularly in the "towne center" type shopping malls around here) with internal streets that are named where the directions should use the name on the sign.
However, I guess the question here becomes whether named street in a large shopping development are really "parking lot" roads.
My first thought was the lot here
which was entirely parking lot segments but has internal street names. However, I see that editors have already changed most of the named streets to "street type." So your proposal should now work fine here.
My second thought was the lot here
which again has internal street names (and is admittedly over mapped). But again here the named streets primarily use the "private street" type. So again your proposal should work.
So I guess I'm wondering whether we shouldn't propose to waze the criteria "do not not announce the street name if the next segment is a parking lot segment." And then, if waze adopts the proposal, promulgate an editing guideline that if a street actually has a name it should not be a "parking lot" road, but rather should be a regular street or a private road, depending on whether it should be use for through routing or not.