SUMMARY: Registration fee rankles some medical marijuana proponents, but hardly is unreasonable. Adam Smith famously said there's no free lunch, meaning everything costs something. Were he in Montana today, Smith might add that there's no free pot, either. A story first published in the Dec. 22 Missoulian and since found careening around the world through the Internet quoted a backer of Montana's new medical marijuana law complaining about the registration fee for people signing up to make use of marijuana to alleviate pain and other symptoms from serious illness. That fee is $200. "Extortion," declares one participant in the marijuana.com...