rewards come in various flavours. i think some ppl say pco/ectm is "good as cash" due to the ease of redemption. most ppl spend more frequently at those partner stores then on hotels, flights or eligible travel spend. i don't consider pco/ectm to be cashback. major issuers usually can cut a chq on cashback balance rather than print as statement credit. i think the differentiator is cashback is not limited to any retailer or spend category.
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