But that's not the only privacy problem.
You can map it easily - the customer knows to which address they paid you. They will eventually see other income you receive because you join the utxos. They see your whole revenue basically.
Clustering is easy and they can watch you...
Unless you really know what you are doing (and forgive me, but it seems you don't), you'll get doxxed to customers and to the merchants you pay at the same time.