I've never come across any statement like his before. Like you my reaction would be to think it is some sort of scam to get you to purchase more of their cartridges. Go elsewhere.
Why don't you fill your own, I do, for both my Epson and Canon. It's the cheapest way to do it. I have a pack here, that I bought sometime ago, it contains four colours, each of 30ml and a syringe. Full instructions are included, this pack was £2.99. I was a late starter, because I was told it was messy. But if you have more than 2 brain cells to rub together you shouldn't have to much trouble getting the hang of it.
Here's a tip, for best results. You have to start filling before the cartridges run out of ink. Because they are chipped. So if you let the cartridge run out of ink you can't use it anymore.