The issue of shipping charges is one that will never die.
The way I see it, if someone charges above what you might think is reasonable, don't bid on the auction.

I think you will agree that in some cases the purpose of increasing the shipping charge is to avoid paying ebay the commission.

I suppose one could say that anything over 61 cents is high being that bubble envelopes cost about 12 cents and postage is 49 cents.

I think in fairness, one has to remember that time is money, ebay charges a commision for both listing and selling. Couple all that together and it is difficult for a seller to make a profit.
It is for these reasons that I personally have never sold anything on ebay. It's just not worth my time.