returns are not universally free or easy. I bought a power supply for a computer (corsair) and it went on sale a week later. I called to get a price adjustment

returns are not universally free or easy. I bought a power supply for a computer (corsair) and it went on sale a week later. I called to get a price adjustment and amazon told me they don't match even their own prices. So I said I'd return it and order a new one and I was told I'd have to pay return shipping. I don't buy many products on amazon anymore.