Thousands of empty customer records created every day

public virtual Customer InsertGuestCustomer()
        {
            //KEVIN NGUYEN - get current IP address
            var currentIpAddress = EngineContext.Current.Resolve<IWebHelper>().GetCurrentIpAddress();
            if (CommonHelper.IsValidIpAddress(currentIpAddress))
            {
                var guest = _customerRepository.Table.Where(x => x.LastIpAddress == currentIpAddress
                                                    && (x.Username == null || x.Username == string.Empty)
                                                    && (x.Email == null || x.Email == string.Empty)
                                                    && !x.IsSystemAccount)?.FirstOrDefault();
                if (guest != null)
                    return guest;
            }

            var customer = new Customer
            {
                CustomerGuid = Guid.NewGuid(),
                Active = true,
                CreatedOnUtc = DateTime.UtcNow,
                LastActivityDateUtc = DateTime.UtcNow,
                LastIpAddress = currentIpAddress
            };

            //add to 'Guests' role
            var guestRole = GetCustomerRoleBySystemName(NopCustomerDefaults.GuestsRoleName);
            if (guestRole == null)
                throw new NopException("'Guests' role could not be loaded");

            _customerRepository.Insert(customer);

            AddCustomerRoleMapping(new CustomerCustomerRoleMapping { CustomerId = customer.Id, CustomerRoleId = guestRole.Id });

            return customer;
        }