I'm doing something similar with walking. Trying to walk instead of busing as much as possible, plus adding in extra walks. So far it's going really good. I missed 2 days of walking because I was mostly camping and there wasn't any walking/busing opportunities.
But for the other days I've averaged walking 6.9 km (4.3 miles) / 80 minutes a day. I'm feeling the same way about busing that you are about driving. I bused to work today as I plan to walk about 2 hours this evening. But it felt lazy and annoying.