A sale is a sale, but where the money landed matters for your books. Cash in the drawer, money in a mobile wallet, and a card settlement into the bank are three different assets — and a bookkeeping system that records all of them as "Accounts Receivable" is quietly telling you that you're still owed money for a sale you were already paid for.
Done correctly, a fully-paid cash sale increases Cash. A fully-paid mobile money sale increases the Mobile Money account. Only a sale where payment hasn't happened yet — an invoice, a tab, a delivery-on-credit — should touch Accounts Receivable.
This distinction is what makes your Cash Flow statement and your bank reconciliation actually mean something. If every sale defaults to the same account regardless of how it was paid, those reports stop reflecting where your money really is.