It's not unusal for someone to be stronger in one area compared to the other. There are many individuals who thrive on kata competition at the national and world level, and I certainly wouldn't want to be in a fight with them in a dark alley. For example, someone the likes of Clay Morton, is an excellent example. He's a world champ at kata, and I'll bet dollars to dimes that he can certainly do well in kumite.
You also have excellent kumite folks who spend more time on their kumite, than their kata, since they know that is where they thrive. Someone the likes of Tommy Hood (now a coach with the US National Team) has always been known as an excellent kumite practitioner. Despite his excellence in kumite (or maybe because of it...), his kata is as solid as any, and I've always enjoyed both his kata and kumite clinics.
I'm not going to kid anyone... My stronger points in competition are in empty hand kata, as well as kobudo. Even if my sport kumite isn't as good as the upper echelon, rest assured, I'm going to give you a good match, and win more often than not. When someone says "your kata is better than your kumite," I simply think of it as reinforcing that which I already know.
Just enjoy the competition, and train the way you want to train. As long as you're happy with what you're doing, then there's no sense in wasting precious calories over one person's opinion.
