However, as libertarianism has become popular, more and more there are socialists (leftists, "democrats" and "liberals") who are deciding they are "libertarians" without understanding what libertarianism is.
Libertairans -- and this is what defines the movement-- are people who agree with the Non Aggression Principle. (aka NAP) In fact, to be a Libertarian Party Member, and get your card, you had to sign a pledge that you subscribed to the NAP.
Show us how Monsanto is violating the NAP, and a libertarian will agree that Monsanto should be held accountable for the crime.
Libertarianism isn't really so much about hating, or loving various companies. It is really about enforcing the NAP against anyone who would violate another's rights using violence.
Sometimes this includes companies as well, but we're pretty resistant to the piling on that a lot of people do. (e.g.: "I hate monsanto, therefore cloudand is evil").