Because it's fun. And amazing. But then I also think a radio controlled plane that could fly for 20 minutes on rubber bands would be cool and a homemade working vacuum tube from a lightbulb and porch screen would be amazing too! Also the "better with a lens" part is very subjective... it won't make a better pinhole photograph! Don't worry not deterred and not offended... slightly bemused that you don't see the value and "wonder factor" of these things.