In many parts of the world, that's absolutely a thing grandpas do :)

Totally. An Austrian fellow (who was indeed a grandfather) we rented a cottage from did this and told us about when I asked about what he was going to do with the hundreds of apples falling from his ancient apple tree. Apparently it's legal there to distil your own eau de vie at a non-commercial scale. We went home with a complementary empty plastic water bottle filled with his Schnaps.

It used to be a thing in the Netherlands too, but the lack of legality made that a much less popular hobby.