There are lots of gravitationally attractive resoures scattered throughout the asteroid belt.
In a couple months like, what, once every 10 years or something when it's closest to earth? Otherwise iirc it takes much longer
Only 26 months in the Earth/Mars system, in fact. And that's still the fastest way to go, which is the only thing that's relevant for crewed spaceflight. Doesn't matter how much you're saving on gas if you still need to bring enough snacks for the drive.