Probably no need to tell you this – going forward, I'm sure you'll keep all your receipts.
However, back to your problem. Through years of experience – I've discovered that when I have something a little out of the ordinary, I call the store manager – FIRST. I only deal with people who are empowered to give me a 'yes.' Don't waste time with people not empowered. I find that when properly explained, without: anger, rudeness and investment in the outcome, you will be helped. Example: I had a fruit juicer which died in a matter of weeks and NOT only did I not have the receipt but I hadn't kept the box. The Walmart manager graciously exchanged a new fruit juicer – without the box – using the box to return my juicer to the manufacturer. Walmart has a comfortable return-to-manufacturer policy on defective/returned products.
At the very least, you should have received new ink jets for the old (making up the difference, if any.) Your experience is really Walmart's loss. You will always have the taste of this experience in your mouth if ever you should shop there again. You will share this with others who will also be put off and lastly I read a statistic years ago, that when only one customer stops shopping at just one store – the loss to the store is in the many, many thousands of dollars over a lifetime.
If they had taken the loss of just a few dollars in taking back and/or exchanging your cartridges, and done it with kindness they would have made a great ally out of you.
Lastly I learned another lesson – never stockpile ink cartridges. I had purchased several on line (far cheaper than in the stores) and my printer died and I was stuck when I bought another type of printer.
As an aside, my local Walgreens now refills ink cartridges. Haven't tried them yet – but I look forward to doing that – as the cost of ink cartridges are now so high!
I hope this helped.