Deposit rip-off/Horrible WiFi
When checking in, in addition to the usual credit card scan for the price of the room, Hilton takes an extra $xx (Expedia doesn't allow me to give the actual #) per night "security" fee. There is no reason whatsoever to take this money other than they are arbitraging it on the backs of the guests. Hilton has approximately 750K rooms and an average fill rate of 75% which means Hilton is arbitraging approximately $28M per day. This is simply stealing.
Additionally, the WiFi is unreliable and weak. While that may seem inconsequential, the fact is that virtually every business traveler is using WiFi in their rooms to work so a poor WiFi network is a significant hindrance.