Credit card processing without a merchant account is a dream of those who are unable to go through background verification because of problematic business history or to provide the necessary data needed for this verification (such as tax ID or SSN). In practice, however, to accept credit card payments, a business has to open a merchant account or go through a rigorous verification process of background checks that any merchant account applicant must go through. A merchant account is a kind of a vote of confidence. It’s also a mechanism allowing the merchant acquirer to mitigate risks associated with fraud and chargeback handling. In case of refunds, or chargebacks, or fraud, the merchant may be insolvent, and the acquirer has to assume the respective financial liabilities. A merchant account is a way of financially protecting the merchant’s customers.
Read more on why it is impossible to process credit card payment without a merchant account in the respective article on Paylosophy blog.