I'm a Holga shooter. I have the manual.
I resist efforts to tell me what my tools are for and what they're about. I think we, each of us, get to decide that for ourselves.
Ok, so I just did the scotch tape thing and it was most amusing. The icons represent roughly 12", 18", 24" and infinity is everything past about 48". In other words, not really consistant with the pictograms. Now I'll know to seldom move it from infinity.
Glad it worked. Now you know. I wish my Holga focused at 12". The closest I can get it to focus, without the lens falling off, is about 2 feet.
...for some people. :) Different strokes, some people care more about focus, even in toys, more than others. You could make the same argument against selecting film with an ISO that's going to actually work in your lighting situation.
There's a gal with a complete tutorial on toycamera.com. What I've done to measure my Holga with some +1+2+3 close-up lenses was to put my Hassy focus screen on the back and look through it. Use a focusing cloth.