CB is legal provided you stay within the required frequencies, power limits and use type-accepted equipment. WPAS appears to use CB equipment and a lot of CB operations (at least here in the USA) are done with non type-accepted equipment...making the CB service a mixture of legal and illegal transmissions, hence enforcement is difficult (in the USA). My understanding with WPAS in Ireland (and the CADS service in the UK, which is functionally the same, and uses 26.965-27.405 MHz and 27.60125-27.99125 MHz (CEPT 40 mid band CB channels and UK FM 40 27/81 CB channels) the transmitter power limits are similar to CB, but, like CB, are rarely actually enforced.
WPAS actually has two sets of overlapping channels (27.60125 MHz to 27.99125 MHz in 10 kHz steps, and 27.605 MHz to 27.995 MHz in 10 kHz steps - this seems to match with the use of "export" or modified CB equipment and/or equipment designed for the UK FM CB channels). From other monitors and logs, Irish churches also use the regular 26.965 MHz to 27.405 MHz "mid band" 40 CB channels for WPAS purposes and ComReg doesn't seem to care. Much like the USA, the 26-28 MHz band is given a very hands-off approach by regulators as long as nobody is causing interference to anything important. Here in the USA, enforcement is complaint-driven and the FCC won't really do anything unless somebody asks them to.
The use of frequencies on what's considered a safety of life band (6 MHz marine band and 12 MHz marine band) means that if a maritime radio user reported interference on 6295 kHz or 12255 kHz, Reflections Europe would probably get a visit from ComReg.