This is not accurate. "Brokerage" is determining the class of goods and reporting to customs for shipment. When you cross the border in a vehicle and the goods belong to you AND ARE IN YOUR POSSESSION, you do not require a broker, you simply declare the goods and country of origin.
When shipping an item, class of goods and origin will determine if the goods are eligible for entry into Canada and if duties and taxes will be applied.
With USPS, you are charged a flat brokerage fee incorporated into the shipping price. When the package arrives at your door, you MAY be required to pay duty and taxes.
With UPS, brokerage fees are over and above the shipping price. When the package comes to your door, you WILL pay brokerage fees and MAY pay applicable duties and taxes depending on the item value and whether or not is was declared gift/sample etc.
To make matters more confusing, some companies will ship UPS but handle brokerage and applicable taxes themselves. Cabela's is a perfect example of this. No surprises at the door when the UPS guy hands over that Cabela's box.