I'd prefer not to have content-free ads on the HN front page, regardless of who is involved in the product. I'd feel differently if there was at least some useful content on the site.
Maybe it's better if it's all grouped under the "Show HN" titles so folks who don't like it can mentally filter it quicker. But I'd be sorry if these posts disappeared.
That said, I think the author should take your point about providing useful content to heart - I think it'd be better for the visitors, but also better marketing.
Any thoughts or suggestions are more than welcome.
Perhaps it'd fit in better as a Show HN.