Motorcycle Superstore ".ca"

I use to buy from Motorcycle Superstore.com for years and was happy with it, however few weeks back when I ordered a part from them I got pinched same way. When I checked out the bill was different than the one in my package and on my Visa. Duty charges and shipping added. Sadly its was my last time dealing with them. Note, shipping was 3 days, very fast.
BTW someone said to me if you check out through .com instead of .ca this charges are not applied , I find that very hard to believe.