if you look at their likes and dislikes in the details screen, you will see that some of your villagers like running
they are rare, so cherish them

ither villagers run when they are running away from something they dislike
the quickest way to a master farmer (without having to baby sit) is to train someone as a farmer, and then turn the game off
the villager will continue to farm and gain points while you are away
otherwise, if youare prepared to babysit, the skill points are gained as soon as the villagers captures (or picks) the food
instead of letting them go all the way to the food bin, pick them up, and put them back in the ocean, or other area--keep in mind they will gain skill, and you will NOT gain food points