Unless you are a freakish sweat machine or your hero is Pig-Pen and you emulate him in every way, no. The trackpad does not get greasy and the keyboard does not get shiny.
Do this and you'll never have an issue:
1) wash your hands
2) occasionally pre-moisten a lint-free towel with glass cleaner and wipe the trackpad, kbd, and screen.
In other words, clean up after yourself and you'll be good.