While I do agree that someone who has brownies made for them should not argue much with the maker of said brownies, I do feel it is fair for the consumer of the brownies to argue a point that is so very very wrong.
Brownies are good, there is no denying that. Milk cannot make the brownies better. Milk can certainly enhance the brownie eating experience if you are one who enjoys milk. You see, the milk is enhancing the experience, not the brownies themselves. A brownie is pure goodness with or without milk. Drinking milk might make the eating of a brownie better, but does not change the fundamental nature of the brownie.
There are few constants in this universe, few things that we can consistently rely on, but the goodness of brownies will be a truth until beyond when the sun dies.
Also, milk is vile.
xoh
p.s. you should invite me over to eat nachos and watch more of the world series. Just a suggestion.