Ah... but their BOTS don't read. So if you have a Discount Code box, write on that page... Enter the code "BOOKDIRECT" for 10% off. The bot... can't do that
There is also the parity rule that says that it has to be the exact same thing. So if you offer a different package, they can't compare. For example, a bottle of wine in the room when they book direct... well, it's not the same anymore.... so they aren't comparable.
And of course, you could offer your rooms online as Run of House, versus allowing people to book specific rooms directly. So if they want a specific room, they have to book direct... if they book online, you can choose which room... move them around, etc. I get emails from them asking if they can specify a room and I reply that they are only finally assigned on the day of arrival.