But I contacted SBA.gov and they said I wasn't required to pay the taxes for just supplying customers in New York with products from other states because its mailorder.
Quit arguing about the definition? I'd rather not.
PHYSICAL PRESENCE -
Do I have retail facilities, a warehouse or any office space in New York? Maintaining retail or warehouse facilities will give you physical presence. Also, having an office for employees, even for business activities unrelated to mail order sales, will give you physical presence.
Do my employees or I enter New York for purposes of taking and transmitting orders from New York? If your employee or independent contractor go into New York to take or transmit orders your business may have physical presence in New York. However, contracting with a common carrier to deliver mail order goods does not constitute physical presence.
Do my delivery vehicles frequently enter New York for purposes of delivering property? Frequent deliveries in New York by your trucks will give you physical presence in New York. An occasional delivery, however, may not constitute physical presence.