EDIT: If someone wants to link some laws that's be useful.
For the downvoters: I am clearly NOT saying it's okay to hide cameras in an AirBnB. But it's probably not a criminal offence. The police have no power here. I'm NOT saying it's lawful -- the AirBnB owners are probably violating Irish data protection laws. But again those are not enforced by the police. In the UK it's not a criminal offence unless it meets the definition in the sexual offences act 2003, and putting cameras in the living room but not the bedroom probably gives the owners enough deniability to avoid prosecution. https://www.legislation.gov.uk/ukpga/2003/42/section/67