N Rotteveel/iStock Editorial via Getty Images As El Salvador adopts bitcoin as legal tender, the shift to a technology focused on decentralized finance could have implications for companies that get paid to move currency around the world. Bitcoin's Lightening Network is designed to enable rapid transactions at very low costs. If transfers flow through this blockchain transaction network it will enable a new payment system where transactions are instant and fees are little to nil. MoneyGram (MGI) shares are down 14% this week, but its $100M at-the-market equity offering may also be a factor. Rival Western Union (WU) is essentially flat. To be sure, MoneyGram isn't sitting still, announcing last month a partnership with Coinme to allow customers to pay for bitcoin with cash and withdraw bitcoin holdings in cash. As per Coindesk, Carlos Miguel Rivas Carrillo, attorney and founding member of a fintech association in San Salvador, shares his concerns for