If your hotel room has a mini-bar, check to make sure that all the bottles are sealed as soon as you arrive.
Some guests drink the beverages and refill the bottles with water or tea to avoid the high charges. If this goes undetected by hotel staff until after your stay (they do check for it, but aren’t necessarily always diligent about it), the items will be charged to your credit card.
If you find unsealed bottles, report it to the front desk right away.