Let’s say you’ve got a group of people who are trying to get a company to change the way it does business. There are two different ways in which their efforts might qualify as “political”:
… they might be trying to coerce the company by bringing down the government to enforce their demands against the will of the company decision-makers (or by getting the company to accept those terms under threat of government action).
… they might be trying to encourage the company to voluntarily accept their demands by coordinating conscious efforts to change people’s decisions in the market so that they intentionally act in such a way as to give the company an incentive to change how it does business—e.g., strikes, boycotts, letter-writing campaigns, shareholder actions, etc.
Now, whether (1) is objectionable from the stand-point of Austro-libertarian principle or not depends on whether the resort to government force would be defensive or aggressive. There are cases where it has been defensive (the CIW, for one, has exposed and broken up some honest-to-God slavery rings in the Southeastern US in the course of its work over the past few years), but clearly the demand for Taco Bell to work with its contractors to secure higher pay for tomato-pickers isn’t one you could legitimately get the government to enforce. Fortunately, the CIW has never, as far as I know, followed any kind of strategy under heading (1). The Taco Bell Boycott, specifically, was certainly never a “political” campaign in that sense. (And you can’t run the standard “government-sponsored cartel” objections to unions against CIW, either. CIW doesn’t have any government recognition as a union and couldn’t get it if it wanted it.)
Whether (2) is objectionable from an Austro-libertarian standpoint is a lot more complex and I can’t see any plausible principled reason to say that “political” campaigns in sense (2) are always unjustified. It’s not enough to just point out, “Hey, group A is placing demands on firm B and engaging in market activities that hurt B’s bottom line until B complies with the demands” and close the books on group A’s campaign; people—and for that matter firms—do that all the time, sometimes for good and sometimes for ill. People boycott contributing to their alma mater to get foolish policies changed; firms and individuals refuse to deal with companies that deliver shoddy goods or engage in sharp dealing unless or until those companies show that they’ve changed; workers leave firms—sometimes en masse—if they aren’t treated right or aren’t paid enough. Whether these are good or bad ideas depends in part on whether the complaints that the people have are legitimate, and in part on whether the tactics do more harm than the good that can be reasonably expected from them at the end of the day.
You could, of course, try to make a case that the CIW’s specific demands are unfair and/or stupid, or that the strategy they adopted was more destructive than constructive, but what’s the argument for that conclusion?