Of course, OP could take the secondary (non-toll) roads. Will see a lot more of Japan. Also get lost more and be much slower, but you discover some great places that way. I once drove Route 4 from Hachinohe down the east coast to just north of Tokyo once and it was great. One of the best road trips I've ever done anywhere on the planet. Also took almost 2 weeks to do those ~700km, but then, I kept stopping everywhere.