More than 300,000 people have watched a quirky music video peppered with complaints about the discount food store chain Trader Joe’s on YouTube.

The video takes shots at its crowded parking lots, once-popular items that it no longer carries, and its 10 brands of soy milk “that all taste the same.”

Knowing those facts, it would seem as though Trader Joe’s wouldn’t be happy with the amateur video recorded (against store policy) on a cell phone.

But marketing experts say the video is a huge win for Trader Joe’s because those complaints are included in a real-life piece that also praises its charms.

“I’m pretty sure the Trader Joe’s messaging guidelines don’t include complaints about the parking lots or the stuff you want that’s not in stock,” writes Jeff Brooks on Donor Power Blog. But that’s precisely why this is such a great video. “It’s not marketing. It’s relationship. Relationships are multi-dimensional. They include positives and negatives. In a good relationship, the positives outweigh the negatives.”

Mr. Brooks writes that supporters are more likely to believe messages that point out both the positives and the negatives about the organization. The message becomes more authentic if it includes both sides of the story — and it is likely to be more memorable.

For nonprofit groups, the message is simple — don’t be afraid to empower your supporters to talk about your organization, even if they aren’t 100 percent positive in what they say.

“It might tell us not to be afraid of what donors and supporters say about us in public, even if they complain,” Mr. Brooks says of the video.