I feel that the applicability of the "do one thing and do it well" philosophy scales with the frequency with which you expect to do that thing and the complexity of the task. In the case of a text editor or a VCS it obviously makes sense. In the case of tools that I use a couple times a year like these, having them all grouped together under a 'misc' application is exactly what I need in order to waste time fumbling through my installed apps trying to remember where I left the QR code generator.