Had I known fully how sweet the unit was Bob before I ordered my Gen2 Lowrance gear, I would havce gotten one for sure That being said, I do not have one here to play with but common sense allows me to answer your questions with some confidence.
It is not just your finger that can access a touch screen, look at an iPhone, same deal there. It is just a point of pressure that is read by the touch grid.
You don't dry your hands to use the same iPhone and being a marine unit I can assure you it is built for function and use within the marine environment.
Pushing a button on a screen or usualy keypad is no diffferent, if you can access your keypad buttons you can also activate buttons on a touch screen.
Now, should I call Navico and change that order or not? Hmmmmm.