Room service tray and/or cover charges annoy me the most. Common at IC Hotels around the world -- though most IC Hotels aren't luxury calibre -- as well as The Waldorf Towers in New York and (surprise) the Four Seasons San Francisco.

$4.95 tray charge, $1.50 per person cover charge, plus taxes and gratuity (which is usually gratuitously added for my convenience) does make one think twice about ordering room service. It is even cheekier when one sees a gratuity line on the room service cheque!!

On the other hand, being utterly and completely ripped off is equally annoying...... like 9 Euro Diet Cokes or 25 Euro spaghetti bolognaise to $20 club house sandwiches or $12 cheesecakes.... certainly more than nickle and diming...