Is the ad deceptive? In the US - maybe.
Because the selling company is directly providing the product and service, it can use the claim, but only for a limited time. It may be illegal, however, if that offer is continually used. From
http://www.ftc.gov/bcp/guides/free.htm
(h) Frequency of offers. So that a "Free'' offer will be special and meaningful, a single size of a product or a single kind of service should not be advertised with a "Free'' offer in a trade area for more than 6 months in any 12-month period. At least 30 days should elapse before another such offer is promoted in the same trade area
Not sure about Canadian law.
There's a big difference between directly selling and shipping a motorcycle part (a specific item that is always the same) and a flower arrangement brokered to a third party for fulfillment.
The filling agent (delivering florist) is not obligated to provide the claim and can freely reduce the size of the delivered product to offset their delivery charge. In fact, there is no national 'regular price' only a 'suggest retail price.' WS's are specifically forbidden from requring members to sell specific products at specific prices so their agents/order-brokers have no basis for any 'free' claims except possibly in the area of service charges. And even then, they cannot be offered continuously (see above).
If a product or service usually is sold at a price arrived at through bargaining, rather than at a regular price, it is improper to represent that another product or service is being offered "Free'' with the sale. The same representation is also improper where there may be a regular price, but where other material factors such as quantity, quality, or size are arrived at through bargaining.
If your parts company transferred the order to another company that substituted a smaller or knock-off part to offset their cost of shipping, that would be illegal....
Think about it - Why do you rarely see large companies using 'free delivery' as an ongoing claim? Because they are in the crosshairs of both government regulators and their competitors.
I doubt you'd want to turn in one of these parts suppliers, but one of their competitors might.