I agree with you. Depending the volume that you ship every month, small business shipping rates can be negotiated. The more you ship, the more leverage you will have when negotiating for a lower rate. But don’t assume you’re too small to qualify for special rates or discounts.
The best advice I can give is to compare each alternative. Each service offers different programs for shipping for small business and the best way to get what you need is to call and speak with a small business shipping consultant.