"Just trying to understand why bother?"
Without bitcoin miners, bitcoin dies. Transactions are not processed. Everything you're holding becomes worthless. That's why we bother.
It's also a fun hobby for us that makes money. We enjoy the technical aspect of it as well as supporting the cause. That's also why most of us are DOS'ing UPS's tracking site wondering when customs will get done installing their custom spy chips. LOL (really, I'll be watching where these go)