I remember being confused when learning this word on WK, wondering when will I ever encounter such a strange word like “return to origins” … and ironically, for the past 6 months it’s in the top 5 of words I see everyday ! Because every major shops in Japan are participating to this campaign, so it’s plastered everywhere:
It’s a 5% rebate on consumer tax when using cashless payment. So it’s a nice use of 還元, some part of the money “return to origin” (the payer).