Yes, they can be refilled. They are chipped in the same way as the single ink cartridges for larger Canon printer models. No resetter exists but the ink level indication can be disabled allowing you to print with refilled cartridges, just as with the larger models before the resetters became available. Here is a Google translation of an old druckerchannel.de article that is still useful as the cartridges are older but very similar. Here is a description of the cartridges with refill instructions in English and instructions for disabling the ink monitoring from a German ink seller.
One would assume that the inks for the Canon ink tank printers would be ideal for refill as the Canon ink tank printers are based on the two cartridge printers. I tried using such ink for refilling a black cartridge, but that was no success, see this and this. What worked well for me was Image Specialists ink from Octoinkjet UK, see this post.
You are perfectly right in one respect, but you spend a little buying the printer and it costs a fortune to keep in in ink..
I also used my A3 printers for my daily printing till I discovered the Maxify..