Goal: Buying your own drinks, milk, and cereal is a great way to save money when travelling. A potential fly in the ointment is hotel mini bar sensors that charge you if you move any of their items out of the hotel minibar (In the US, minibars now often have sensors that detect moved items).
Solution:Lots of hotels will lock the minibar and supply a separate fridge for you if you ask. Ask in advance as they sometimes run out of mini fridges. In my experience, there is usually no charge. I ask for the mini fridge to be put in my room for when I arrive. Except, I’m usually too embarrassed to ask so I get the Visa Concierge to sort this out for me!
Solution for budget hotels where there is no hotel minibar:
In the US, places like Motel 6 might not have a minibar but may have an ice machine on each floor. There will usually be a plastic bucket in your room that you can take down the corridor to fill with ice. You can also just fill a bag with ice. This makes a workable solution for keeping items cold. You can put a plastic bag around the item you’re trying to keep cold to stop water getting in as the ice melts.