Booking get 15% of the transaction so it makes sense to ask for 10% off when calling the hotel directly (which increases the profit of the hotel by and saves you some).
Eccept that is breach of contract with the booking service and can cost them the contract[1]. Since everyone is using booking.com or hotels.com, they will quickly shut down due to no customers. Hostage situation.
[1] At least last time I looked into it. Haven't had a change to travel since a few years.
I just tell them that I saw a better deal on gestures broadly the Internet and they give me some discounted rate.
This happens all the time with every single type of service provider, why would some shitty service like Booking.com get to mandate no one can offer any other discounts?
What, just because there's some sort of aggregator service out there that you've partnered with you are not allowed to offer coupons, discounts, or your own booking services yourself? I would find that VERY difficult to believe.
Plus, based on what we're hearing everywhere, potentially losing your contract w/Booking.com seems like a blessing.
[1] At least last time I looked into it. Haven't had a change to travel since a few years.