I've ridden for decades in cities that had lots of traffic and little in the way of bike paths. I enjoyed it and it forces you to learn some useful riding skills. I now live in a city that has invested in an extensive system of bike paths. I like them a lot. What I really like about them is that it gets ordinary people to show up on bikes often without helmets and fancy gear. It really helps out people with small kids get out on bikes when they would understandably be too freaked out on the road with the little ones. It helps create a constituency for bicycling. The advantages of bike paths are clear.