Sheer availability/afffordability comes into play somewhat there, Smith. In the US, at least in some parts, ganja isn't or until recently hasn't been...widely available, and when it is, smoking a huge joint all to yourself is oftentimes overkill, expensive and unnecessary. Considering true US quality high grade can creep up to 400 US Dollars an oz, people like to be a bit conservative in their use. When you can buy a QP or more for $40US, the quality will be less than that found in the US typically, but sheer abundance makes rolling a joint the size of a baby's leg a lot more fun, and you don't feel nearly so inclined to share, when there's plenty for anyone else present to roll their own if they feel like partaking. At least, thats MY take on things....