I don't think it's stupid.
For one thing it's a learning experience for those doing it. Maybe they find out they're really good and go on to be hardware/games developers. Understanding something is rarely a waste of time.
Lots of good things have come from playing about with things like this.
One example, someone wrote software to allow you to edit Miis on your PC. This allows you to change the owner of a Mii so you can edit it on your own Wii as well. It's not perfect (see
here) but it's better than the nothing we would have had if they inventor had said "Why bother with that, that's not what it's designed for, ergo it's stupid"
Another example that looks like being really good is a Sega Saturn Game, Shining Force 3. Only part 1 ever got translated into English and so only part 1 saw a European/US release. This is still my favourite RPG of all time and at the moment people are working on hacking into the game's code to
create an English version. It's taking forever because there's so much text but it will be a tremendous achievement. I have already bought the Jap version (you'll need it to apply a patch that does the translation) and plan on buying another saturn and getting it chipped just to play Scenario 2 (yes it's that good a game!).