Georgia amateur radio operator Malcolm Richardson, WC4RAV shares this link to the Georgia Dept. of Motor Vehicles (DMV)
The link reveals Georgia DMV has no fees for ham plate. California DMV charge for manufacturing the plate. Only California DMV has change policy in Nov. 2007 and started making plates with spaces in them for new applicants as well as replacement plates. Callsigns do not have spaces in them. Callsigns are governed by international treaty. California DMV has stated it is required only to press the letters of the calls in the sequence set by FCC but it has administrative authority to add spaces for the law does not say it can not put a space in them. California DMV has ruled callsign plates without spaces are vanity plates and therefore are subject to vanity application fees, plus yearly vanity fees, about $40 and upward depending on options selected. Georgia had no fees.
Malcom continues and says:
An easy fix would be to issue a sticker with the words "Amateur Radio" (similar in appearance to the Georgia plate) to when a vehicle is reregistered yearly for plates already produced. For plates in production the text can be pre applied.
This way officers know 2 things: that the plate is not a vanity plate - and to run them as Ham tags - and that operator is licensed to operate radio equipment possibly exempted from some laws regarding radio equipment. This should do away with the ridicules practice of place a space in a call sign .Which in my opinion would make it more difficult for an officer to determine that it is infect a ham plate.