From Ballotpedia
San Francisco, California:
Tim Mooney, partner in Silver Bullet LLC and pioneer of the signature bluff strategy, brought an idea into the limelight about lobbyists being a threat to the I&R process at the Global Forum. Mainstream I&R activists have always focused in on state officials being the biggest concern.
His explanation was that lobbyists who engage in social activity with the legislatures are able to do just as much as, if not more than, initiative & veto referendum petitions.
See also