There are 3 issues: The most important one is few business are setup to make a direct ACH Credit (for making an ACH Debit its an harder barrier and even fewer

There are 3 issues: The most important one is few business are setup to make a direct ACH Credit (for making an ACH Debit its an harder barrier and even fewer businesses have it ). Those that are have cumbersome UI/UX. The other issue is giving out your account number is not always a good idea unless you trust the source. And finally if you do give out the account number and make a typo then the money goes to the wrong account. Alternately the account number needs to be verified. Which is why even today paper Checks are still prevalent by the billions. You can try Digital Checks though.