I really like your point here, all the disucussion about open source license always makes me wonder how applicable that is in the real world. What it comes down to is that a lone software developer doesn't generally have the resources available to enforce his license, making it rather pointless.
He has. There are projects like http://www.gpl-violations.org/ and people like Harald Welte (and many more) who do have the resources and who will help you (for free).
True, but that mainly helps when it's the body of code that provides the key value, like in a large engineering project of the Linux-kernel variety. If it's the idea and algorithms that are valuable, and the code is a fairly straightforward implementation, then someone can just reimplement it and there's no GPL violation (subject to some gray areas). The only thing that could really keep that from happening is: 1) keep your methods secret; or 2) some variety of software patent.
