I'm not surprised in the slightest that printers work this way.
Of course, the free market that makes many printer companies want to create proprietary, expensive cartridges is also the same free market that made Epson make the CISS system you refer to. It's all about doing the research and finding out what's not heavily advertised...and which company is trying to undercut the market by innovating, rather than maximizing profit in a predatory way.
Fearless creatures, we all learn to fight the Reaper
Can't defeat Her, so instead I'll have to be Her