Way back in 2011 the Adobe Tax alone ran $75,000 a year just to sign up.
https://the-digital-reader.com/2011/...obe-tax-today/
O'Reilly didn't pay that but since even the smallest of independents quietly paid it, it mustn't have been too out of line with their other costs.
Which makes sense since they'd likely need at least a handful of full time employees which in the tech arena means something in the the $50k-100k apiece.
Add in servers or AWS hosting costs, server software licensing, payment processing...
It's a safe bet the store cost them in the low six figures at a minimum. Low seven figures is not out of the question. That cost has to be spread across the total number of units sold by the store itself and then compared to the cost of simply uploading the master files to an ebook retailer.
The way the mainstream ebook market has evolved, most consumers go *solely* through the big stores. Even Baen had to adjust their business model and pricing to tap into that channel.
With O'Reilly selling through the stores and their own site they know how the split works and it sounds like the mainstream stores have been soaking up the bulk of their sales at a time when non-fiction book sales are declining across the board. That left them two options: pull out of the stores and force users to go through their store or close their own store.
One channel had to go and the one bringing in the smallest number of sales lost.
As the article at Nate's made clear, the problem isn't the mainstream ebookstores: it's the internet. The market is splitting into two: those that truly need professional grade information and can afford to pay for it on an ongoing basis (SAFARI) and those that can't afford it or can get by with "good enough", which can be found free on the internet.
Technology disruption hits tech companies, too.