We do not. It is high-risk for both the author and the publisher. More than 80% of books on the market don't make enough to cover the advances the authors have received. That is, realistically, the only money the lion's share of authors will ever see, whether it's $500 or $5,000. It's a sad fact. Big publishers will give you 10-15% of net sales, but it's a moot point until after the book has made a large enough profit to pay back the advance. (That's what the word advance means, you know - money in advance, and it must be reimbursed.)
Agents take 15% of the advance an author receives, so that needs to be calculated by the publisher and the author in the case of asking for and receiving an advance. Agents "respectfully decline" to work with small publishers like us because, quite frankly, there's no money in it. We, as a small publisher, "respectfully decline" to work with agents just because they are in it for the money. That is a bigger concern to them than the author's work. For authors, these works are their babies. We are aware of this, and it is for this reason we cut out the middleman and work directly with authors.
No advances = bigger royalties realised by the author.