Pro-cannabis law reform advocates are continuing to occupy positions of power in U.S. politics.Investors in marijuana companies are an optimistic bunch; they need to be, as the industry is beset by struggles, and even its most prominent companies routinely post net losses. That's why they tend to trade weed stocks up whenever even slightly positive news hits the headlines, as occurred on Monday. The relatively prominent Curaleaf (CURLF 2.42%) saw a decent-sized pop of more than 2% to its share price that da ...