Just from a practical perspective many times the Chasunah is not in the same city where the new couple are planning to live. As such often going to their own apartment is not possible.
From a Hashkafic perspective I’m not sure what is wrong with going to a hotel. Most Chassanim and Kallahs do not go to the cheaper hotels/ motels (the ones where you might stay if you got stuck somewhere) they are going to higher class places that usually have a certain amount of decorum in the lobbies and public areas. We send them to these same lobbies to date so why shouldn’t they go there to stay once they are married?