Well my 24-70 is still available if you're interested to buy it off my hands
Yup some of the food shots were taken with the 24-70. Like some of the CSers have mentioned about the focal length compression, so really see what you want to achieve.
IMHO the 24-105 would be a better general purpose lens, used to own one and kinda miss it due to the weight and versatility as compared to the 24-70(of course you will lose a stop but kind of compensates with the IS and with the 6D ISO capability)
Anyway either lens you wouldn't go wrong, guess you'll have to keep playing around with different lenses to know which one would suit you best.
Hope this helps!
Cheers!