Currently, I am working in an office supply store. Each month a brand of pen is featured at the register and are sold individually. This is a good way to observe pen testing habits. Under less scrutiny, in other parts of the store, test drawings at times include anatomical studies and the kind of writing reserved for bathroom stalls. People behave much differently when they feel they are being watched. At the register customers are mostly determining if the pen works well. My hunch is that writing and highlighting are effective uses for these pens. Other uses exhibit marginal quality (e.g. lack of: permanence, line variety, etc.), whereas for drawing, decoration, and other activities art supplies would likely be a better solution. I did my own testing to gain a better understanding.
Among other scribbles, my trials included drawing a face on one of the scratch papers. Hoping customers would "improve" my drawing, I waited for others to add content. However, a curious thing happened, people no longer wanted to use that test sheet and would skip to the next page. My thought is that either people are uncomfortable with the idea of defiling a human/animal form (particularly when they might get caught), or they often want their mark to be both unique and anonymous. Generally, drawing in public seems to dramatically change habits. I wonder how knowledge of this inhibition would yet further change one's drawing sensibility?