i don't know what they do here, but it was pretty normal to book hotel rooms for our office parties/bridal showers/birthdays back home. especially since we have corporate discounts at certain hotels.  

people who should not drink and drive, or those who no longer have the presence of mind to get themselves home, can stay over. really drunk people can have a decent bathroom to puke in (without being such trouble to the hosts as in the case of home parties). nothing wrong with that.