A minibar looks like a small refrigerator and functions as a retail outlet with no staff. Making that work requires a counting system, and the choice of system shapes everything else about it.
Counting was originally done by eye
The traditional method is a daily physical check by an attendant working a route through occupied rooms, recording what is missing and replacing it.
Charges are posted from that count, which introduces a delay between consumption and billing and a dependence on the check happening before checkout.
Guests leaving early frequently depart before the room is checked, which is the origin of the charge that appears on a card days later.
Sensor systems moved the count to the shelf
Automated bars detect when an item is lifted, and many post a charge only after the item has been out of position for a set interval.
The delay exists to allow for items picked up and put back, which was the most common complaint under the older manual system.
Because the register is continuous, the restocking route can be driven by what the system reports rather than by visiting every room.
The restock route is the real cost
Whichever method is used, someone has to carry replacement stock to each room, which is a labor line attached to a small number of low-value sales.
Stock also has to be tracked for expiry, since items sit for long periods in rooms that are not always occupied.
That combination of labor, spoilage and low volume is why many properties have removed the service entirely and left an empty refrigerator.
The empty refrigerator is a deliberate substitute
An empty cooling cabinet costs nothing to stock, generates no disputes and answers the most common guest need, which is somewhere to keep water and leftovers.
Revenue moves instead to a lobby market with a self-checkout, where one location serves the whole house and stock rotates fast enough to avoid waste.
The tradeoff is availability at two in the morning, which is the one thing the in-room version did well.
Where the format still makes sense
Resorts and remote properties keep stocked bars because there is genuinely nowhere else to buy anything, so the convenience is real rather than nominal.
Premium categories keep them for the same reason turndown survives, as part of a service standard that guests in that tier expect to find.
Practical guidance is unchanged in either case: move nothing you do not intend to buy, and raise a disputed line at the desk before departure rather than after.