I guess I just don't really understand the purpose. If I show up and check in with a card that doesn't have enough funds, they wouldn't give me the room. So how does it do anything for them the day before?
In this instance, it was quite inconvenient for me, as I had informed my bank I would be arriving in Czechia the day that I arrived, and when a charge (particularly a card not present charge) from Czechia went through the day before, the bank decided it was fraud and blocked my card until I called them to sort it out. It just created an unnecessary ordeal and created ill-will with the hotel. Also, between 18:00 the day before and 10:00 the intended day of arrival, they tried to run the card 3 times.