Outrageous shipping fee from Mancini Racing

You put yourself in that position by being put off by needing to add a note for a ship quote 1st. How much again?
Their page their policies. They determine what position you are in and what position you need to be in to continue.

As a final note from me - From seeing what people had to say or didn't say I'll give my opinion on what it seems like to me.

People will spend various amounts of time finding a part and what all goes along with that, before proceeding to check out.
Once they provide their credit card/paypal info and a host of other things they are going to be less reluctant to cancelling an order.

I think they would reasonably expect that they would not be allowed to order unless all charges were presented to them.
The amount of people being less reluctant to cancel after giving info and ordering may outweigh the loss of customers that would be lost when seeing the total cost before ordering.

Shipping costs are high and many people are complaining about them and there are plenty of things and people to blame it on. High shipping costs are expected and there is money to be made on shipping . I'm not surprised to see anyone take advantage of the situation .