The Soda Jerk Works Soda Jerk Works Misleading shipping charges. Internet

I needed a part for my coke machine.  They had it available and the price seemed ok.  I looked for something to explain their shipping charges, since I didn't see any on the shopping cart.  I didn't think it would be free, but when I did a search on their site for the word shipping and nothing came up, I was convinced that it was built into the price of the part.  Anyway, I order the part and the Invoice that was emailed to me, clearly states shipping is $0.  Delivery is listed as best possible way.  There is nothing that states they will compute shipping later and let you know.   The invoice I receive with the part has $7.25 on it for shipping  When I emailed back and asked about it, I was told that the software doesn't compute it and it is on their web site twice.  I couldn't find it.  They said I could send the part back and get a refund, but frankly, I already installed it so I am not going to do that.  Just wanted everyone to be aware of  this little quirk with this company, and don't do business with them over the web.  Call and get the complete price.