All perfect praise be to Allaah, The Lord of the Worlds. I testify that there is none worthy of worship except Allaah, and that Muhammad, sallallaahu ‘alayhi wa sallam, is His Slave and Messenger.
The fact that the state allows the hotels to provide prohibited services does not prohibit cooperating with them and promoting their lawful services, unless one knows that the hotel deals mostly in prohibited things such as immoral parties, drinking alcohol and the like, then promoting them will be prohibited due to what they mostly deal in and because promoting them while they are doing such things is a form of cooperating in their sin and falsehood. Allaah The Almighty says (what means): {But do not cooperate in sin and aggression}[Quran 5:2]
For more benefit, please refer to Fatwa 88774.
As for the hotels whose activities are mostly lawful, then there is nothing wrong with cooperating with them and promoting their lawful products.
Allaah Knows best.