He wasn't collecting address information for US customers, so the invoices hung in a pending state. He didn't check to make sure the integration was working correctly until a customer emailed him to ask why they hadn't been billed three months later, so there were a lot of invoices to clean up, which he apparently found to be very annoying.
Still, the Stripe folks could have at least offered to help him collect the back payments, and (better yet) send an email to his customers taking the blame for this (which would cost them nothing and would reduce the harm to his business).