Interestingly, the D2R2 gravel ride - a fairly prominent gravel ride in Massachusetts/Vermont - has on their website the following:
PLEASE USE CUE SHEETS to navigate routes. Maps and GPS files are for basic reference but may have minor inconsistencies. In true Randonnee style - please use your cue sheet.
If you intend to only use a GPS to navigate the route, please at least take the time to read through the cue sheet pre-ride as it also contains important cautionary information as well as useful route divergence information.
They actually recommend using the cue sheets.
As an aside, I made up my own Google Maps/cue sheet for a ride I did yesterday. I was generally familiar with the area but wanted to do a specific loop and wasn't sure I'd recall it without the map.