Jim,
Get rid of the "Need" word and substitute "technically supposed to have".
The Cheap Beep Project transmitters run on UHF. I put my call sign on each one, unless someone with a Ham license wants their own call sign. I keep my phone and Email current on the FCC data base. I have yet to hear from a helpful Ham that he is hearing one of my beacons.
I keep an open inquiry on the "legal?" silliness. I have heard of neither help nor hassle on VHF or UHF. Marshall has not heard of anyone receiving a "Cease and Desist" letter from the FCC.
My take on it is: Yes, it is good manners to carry a Ham license when operating a UHF amateur band transmitter of any kind.
Regards,
Thomas of the Desert