If you were to follow sales tax law, I don’t think this would not be a Maryland Sale.
For interstate sales with shipment to MD, MD charges a "Use Tax", not "Sales Tax" on the item. You're being taxed for bringing the good into MD for use. See the 3rd paragraph on this page:
https://marylandtaxes.gov/business/sales-use/sales-and-use-tax-information.php