Yes. WotC hired me to enforce their ban on house rules in the contiguous United States (Alaska, Hawaii, and US Territories are contracted out on a case-by-case basis). Anyone who uses a house rule may find me suddenly bursting into their gaming area, slapping the books out of their hands/off the table, and bellowing "No!" while wagging my finger in their face. (I really, really need to be careful when I do this in Texas.)So house rules are forbidden?