As equity investors caught up in the cannabis craze push pot stocks to record highs, options traders are paying the most ever to hedge against a comedown. Skyrocketing marijuana stocks have pushed the $560 million ETFMG Alternative Harvest ETF, ticker MJ, up more than 60 percent since mid-August. At the same time, the cost of options to protect against a 10 percent drop in the fund has surged to an all-time high relative to those betting on gains of the same magnitude.