How could the cost be shown if it is unknown where the item is goin to be sent to?
Did the listing say something along the lines of 'contact seller' about the cost?
Have you asked the seller to cancel because you don't like the cost?
Not knowing how freight works does not make it a 'scam'
And since you, the buyer have all the power, you can not be scammed at all, freight or not
What was the item number involved in this 'scam' ?