A reason to buy a little extra would be simply to avoid going into populated areas (i.e. shopping). I think shopping is a very likely place to contract a virus

A reason to buy a little extra would be simply to avoid going into populated areas (i.e. shopping). I think shopping is a very likely place to contract a virus given the number of times people handle the same items without washing them (think trollies, baskets, food on shelves, checkout machines, etc). That said, toilet paper in general has been driven by media hype 100%. I think I remember some early stories where idiots purchased tonnes of it and emptied the shelves. I think the reason for toilet paper being purchased so much is because of it being randomly reported on in the beginning and that it's so cheap. A person on a modest income could easily purchase an entire shelf of toilet roll, whereas you're unlikely to see such things with higher cost items that have to be consumed within a certain time.