We all know that where there is moisture you are more than likely to have mold, even just a little.
In the kitchen you have potential for mold anywhere moisture is present and temperatures may vary significantly.
As an example: Many homes have garbage disposals that are used quite frequently. Moisture is used to lubricate and the blades turning at a high rate of speed creates friction and heat. What's next, the unit sits to never dry out and mold begins to build.
As well, just like in bathrooms, pipes in walls can generate and help build mold that cannot be seen and many times never found.