Why does using the gradient tool always default to black and white?

[kat]

I have a bunch of gradient swatches, but when I click one and use the gradient tool it always default to black and white. Then I can click my gradient swatch, but that's an extra step.

[R C-R]

The "why" just seems to be because it does, but I can't think of any good reason for that. Even if I preselect a gradient swatch before using the Gradient tool (so it shows my gradient in the large color well), the moment I click to set the starting point of the gradient, it immediately reverts to B&W. It is quite annoying.