Damp is where condensation is likely to form. No place inside of a residential structure should be damp except maybe areas associated with swimming pools or steam rooms.
If the crawl space is damp I would recommend added ventilation and or a heater set high enough to prevent condensation and mold.
The area under a kitchen counter is dry except under abnormal conditions. Abnormal conditions require a plumbing or appliance repair and is not what you wire for.
The commercial kitchen described is a wet location if it gets washed down.
