I'd definitely give them a call & tell them how you feel. Never know, might get something in return or even better your money back from the shipping charge. Companies get you with the shipping, especially when it's a fixed shipping cost. Like it really cost shipping carriers $10 to handle 2 screws. Haha something's a little fishy about that!

If the companies would get there heads out of the sand and ship at a reasonable cost they would get more business.

Shipping USPS isn't any harder to do than using UPS and there is a side benefit, all the boxes for flat rate are free. They deliver them to you address home or business and they pick up the packed package at your address.
I have paid a dollar more for a idem than another supplier but saved $7.00 on shipping.

:D Al