Air-miles, Points, Store or Brand Bucks,Crypto-Currencies, etc.etc are all un-backed currencies with “Counter-Party Risk” (i.e. If the Company goes Bankrupt, or refuses to honor at full value, You lose).
Gold is the ONLY REAL lasting Reward (i.e. The ONLY Real Money)...universally and timelessly, that will never go to Zero, like all the other types of un-backed (i.e. by any Intrinsic Value...like a trade-able Commodity such as Gold) can and will...over time.