The only way to do it - and win here - is to keep the food and beverage receipts where it does specifically mark what is eligible and what isn't (look for the asterisk in the summary section down the bottom).

I've had success with my concierge where the amount is way, way less than the sum of the base room charges. Above that it's a bit of a fight.

The problem is adjustments. Some properties have set up breakfast particularly poorly, where you are earning negative points for breakfast spend (because it doesn't earn points), but the adjustment to make it "free" has negative points.