For the better part of the last year, Visual Art Source reposted a number of the articles that we publish in our monthly digest, ArtScene, as well as in our Visual Art Source weekly newsletter and on our website to a nationally branded website owned and operated by the author of a book published last year entitled Third World America: How our Politicians are Abandoning the Middle Class and Betraying the American Dream.

That author is Arianna Huffington, the website in question being the Huffington Post. After reflecting on and discussing with our writers and editors the array of professional and ethical issues implied by that affiliation, we have made the decision to suspend any further contributions of our writers' work. Accordingly, we published a strike notice.

Two central concerns have troubled us from the start: is exposure to Huffington Post's extensive audience and widely recognised brand simply a fair exchange for not being paid a penny? Is it acceptable for serious writing to appear alongside press releases, shill pieces paid to promote a third party and junk journalism – without anything to distinguish them as such? We went to our writers before beginning to post last year and the response was overwhelming. Go ahead and post. Yet, less than one year later, the reaction to our possible withdrawal was just as decisive in the opposite direction. As publisher, I fully endorse that decision.

Visual Art Source and our partner publications, ArtScene and art ltd, pay our writers for the professional work they contribute. We help them reach many tens of thousands of art professional and fans, and we do not pay them "in kind" for that exposure. Not just because they are paid, but in keeping with the ethos of payment for due diligence, these writers regularly perform as the professionals they are. Their opinions are vested in experience. And because we pay, a standard of quality and know-how is applied to the content that gets published.

And because the Huffington Post does not pay, they invite contributors to publish as much or as little as they like on whatever subjects they like. Does this add up to freedom or mere free-for-all? You decide.

There is something appealing about this – on the surface, allowing for robust free expression as well as the opportunity for the individual writer to build their own audience and opportunities to profit (should they be so inclined). Given the bustle of activity, it's not unlike the street performers at, say, Venice boardwalk, free to attract their own circle of attention and solicit nickels and dimes, which they get to take home.

If I was initially, and remain today, disapproving of the damage to standards of quality posed by the Huffington Post's failure to allow for the slightest distinction between serious journalism or opinion and a press release, it was this quaint analogy cast against the AOL sale that established the true nature of Arianna Huffington's business model. She boasts, by her count, a talent pool of about 9,000 free-of-charge contributors. And that has translated into over $300m. The company payroll for this? Zero.

OK, I understand they have nearly 200 paid employees to programme, edit and administer. Recently, they have raided a handful of Howard Fineman types from collapsing segments of the corporate media such as Newsweek, who, by its own account, the Huffington Post then teams up with fresh-from-college reporters. Congratulations to you, Ms "Abandoning the Middle Class".

This is no union shop. No, indeed, Huffington has approximately 9,000 independent partners working on her sole behalf. For any who fail to see the good humour in this disjunctive equity, as her staffer Mario Ruiz quipped in one case: "How do you resign from a job you never had?" Hilarious.

Queried about the declaration of this strike at the Paid Content conference in New York, Huffington herself was equally sarcastic, though lacking that extra dash of humour that her lieutenant possesses: "The idea of going on strike when no one really notices. Go ahead, go on strike." She went on to make the compelling point that there are plenty of people willing to take the place of these writers. And she is surely correct! This free labour that is easily replaceable is, in accord with her own statement, not very good in the first place. And the new shift? Equally replaceable.

Titans of industry have made this argument throughout our history; there are deep implications in such a statement. And there you have it: precisely why quality editorial content has been devalued and demeaned in that environment. Huffington is correct, and that explains why the overall quality and consistency of content at the Huffington Post is an embarrassment. And I could not possibly have explained it more succinctly than has she.

Huffington has brilliantly and gracefully exploited at least hundreds, and perhaps thousands, of otherwise bright and qualified professional writers. She is revelling in both wealth and celebrity, having been lifted by the combined efforts of this army of the uncompensated. Brava, Madame Capitalist. But as a very public voice, she has suddenly morphed from being a soul sister of progressives into a Koch sister, contributing to nothing so much as that betrayal of the middle class.

We have enjoyed our own audience in this corner of the cultural universe for some time, and have done what we can to cut the writers in on the action because we think it is only right. With $300m of working capital in hand, I can assure both our writers and readers that this piece of the action would only increase. Thus, we have decided to call for a strike of the unpaid, non-unionised and unemployed Huffington Post contributors. Let all writers cease to contribute for now, and until the executives at the Huffington Post negotiate a proper contract with those writers, and establish proper content and quality controls, they ought to deny them the profit-generating benefits of unpaid labour.

• Editor's note: for full disclosure, Comment is free pays for some, but not all of its content; we try to ensure clarity and transparency in our dealings with writers about what is a fee-paying commission and what is pro bono work. As a matter of record, since the author alludes to a statement made by Arianna Huffington at the Paid Content conference in New York this week, Paid Content is a media company owned by Guardian News Media.