But you don't need double entry to register increases or decreases of value; you could as well just use single-entry accounting and add or remove money from a single account, using transactions that are not transfers.
In the past this was problematic because you missed error-checking by redundance, but nowadays you can trust a computer to do all the checking with database transactions (which are more complex checks than double entry, though they don't need to be exposed into the business domain). Any tracking that you'd want to do with double-entry accounting could be done by creating single-entry accounts with similar meaning, and registering each transaction once, if you know that you can trust the transaction to be recorded correctly.
In the past this was problematic because you missed error-checking by redundance, but nowadays you can trust a computer to do all the checking with database transactions (which are more complex checks than double entry, though they don't need to be exposed into the business domain). Any tracking that you'd want to do with double-entry accounting could be done by creating single-entry accounts with similar meaning, and registering each transaction once, if you know that you can trust the transaction to be recorded correctly.