I'm guessing that cops like insurance companies do a lot of the things the same way. A lot of the time we would identify the car for the last four digits of the VIN number. If I was to use RXFE there would certainly be some confusion. To quote the coppers and the inspection guys , If a car was stolen and they go looking for RXFE. you don't want them finding your car and holding on to it till they feel like giving it back. This has been an issue on other cars on bring a trailer.,
especially if those cars end up going to Canada.