To be fair, not everyone is suggesting you need a scripted build system, but you do need some sort of build step, because <script> tags just aren't sufficient for anything beyond a trivial app. (Also ultimately, you do need to minify your code for production).
This build step can just be 'browserify main.js -o bundle.js'. This is where I suggest people start or go back to if they are intimidated by all the various options.
