The problem isn't the cost in money, it's the cost in time and inconvenience. It sort of manifests in two ways. First, I build my professional workflow around a tool that can simply cease to exist in a few days/weeks/months/years...it puts me at the mercy of the maker of the tool, often needlessly. Second, software that costs money tends to be closed source, which is at odds with community efforts that can improve and shape the software over time, as well as maintain it should the original developer move on. So those issues are the problem, not the $70.