Store Shipping Costs

Why is the shipping in the store cost so much? For one $10 item it will cost me $10 to ship it, but five items for a to total of $100 it costs me $25.

Shipping costs are insane and I don't fully understand why.
I order stuff off J-list all the time and its brutal.

From my understanding there's...
-fuel prices for vehicles
--fuel prices for ships
--heavier an object is more fuel required
-prices for differences shipping speeds
--food needs to be shipped fast
-there's competition for capacity through the delivery means
(take the cargo shipped packed 3-4 stories high with crago)
-the amount of labor in handling the product
--things that need care need more human approaches
-prices of objects used to make in location vs your location
-prices of across boarders taxation

Some I could think of. I heard, awhile back, that some of these are manipulated for gain. I dunno anything I can quote so disregard this as a baseless rumor. Would be nice if someone can correct/elaborate on this if need be.

Also, J-list prices are greatly obscured, they manipulate prices and drastically over charge. Guess their excuse is that most of their products can only be bought through j-list since a lot of Japanese companies are against shipping to US.

Not an SD material.
/reported