Indemnity. The Dear Rich Staff believes that the clause you're referring to is either a warranty - in which the artist promises the film does not infringe -- or an indemnity clause - in which the artist agrees to pay for any damages resulting from any claim of infringement. Either way the distributor can likely go after the artist for reimbursement if someone sues. Some distributors don't just rely on these contractual promises; they ask to see the documentation verifying the licenses and permissions.
Fair Use and Other Defenses. The concept of "fair use" is primarily for copyrighted works - the Hannah Montana song -- and not for trademarks (the golden arches). Trademark fair use applies to a different type of defense. As noted above, even if the distributor prevailed, the distributor would most likely have to pay its own attorney fees. So being right doesn't mean that the artist and distributor are free of financial liabilities. Also, you didn't mention if the anti-establishment film is a documentary or feature film. A documentary is likely to provide stronger defenses. (BTW, in today's completely co-opted world does the term "anti-establishment" have any meaning anymore?)
Insurance and Other Odds and Ends. Does the distributor have insurance? If so, you can be sure that the insurer will proceed after the artist and obtain a judgment (and the distributor may do the same on its own). The artist may not have anything of value right now but a judgment will last for many years should the artist earn or inherit anything in the future.
Struggling Artist? We're not sure why the term "struggling artist" bugs us. But really, everyone's struggling to some extent -- even Lindsay Lohan -- and the artist in your question just got a distribution deal which means he or she is way ahead of the game, at least in the struggle-reduction department. Ennyway, just a thought ... and we'll try and get over ourselves.