Once you sign up they have another sucker with access to his bank account! Plain and simple
You grant the Feds permanent direct access to your bank account(s) when you e-file your income tax. Actually the Feds have that access any time they choose to use it. We will see that in operation when Uncle lays on us whatever the modern version of a “bank holiday” turns out to be. Until that time an e-filer should have a separate account in a separate institution for the sole purpose of e-filing.