It doesn't "have" to match anything. Old school thought was shoe, belt, and hat same color, but if you're not careful, you can look like you should be in a marching band. So much depends on the colors of the rest of the outfit. Watch the guys on Tour, most do a very good job of coordinating the colors. Some experts like the belt to match the color of the trousers, it tends to lengthen the lower body. This comes in handy if you have shorter legs and a longer torso.
Personally, I like the belt and trouser match idea in a lot of cases. But if you have special colored pair of MyJoys and a belt to match, go for it! Or even just the extra colorful belt to throw in some spice to an otherwise not exciting color combo. For example, an all black combo with a red croc skin belt. Or a tan or brown combo with an orange lizard skin belt. Whatever works for you.
Just wear what you're comfortable with and don't worry what other people think. Wear your FootJoys and have a good time! :-)