Hedging is not insider trading. Insider trading is trading based on material non-public information in breach of a duty or obtained through fraud. In that sense, it's more of a principal-agent problem.

Also -- hedging is generally not done based on material non-public information, but rather to guard against known risks. Joe the farmer sells a bunch of wheat futures when he plants his wheat, not because he thinks the price will go down, but rather because if it does he goes bankrupt and he'd prefer to accept a known rate-of-return now.