In "the real world of shopping" if you take an item back for refund/exchange do they repay you your costs to get it back to them.

Different scenario, if you buy from a 'real' shop you have the chance to examine the goods and make sure they are what you want so there should be very little chance of taking it back as it is faulty. Same with pick up items on ebay, there is no buyer protection because you should check it out before paying.

With an on line purchase it is different, you are going entirely on the seller's description. If goods are faulty or not as described then the seller does not have to refund return postage however along with many other sellers I don't see why a buyer should be out of pocket because I have made a mistake. If I think the item can be fixed and resold for more than the cost of the return postage I will send them a pre paid, ready labelled click & send satchel to return it in. If it is not able to be re sold I just refund and tell them to chuck it in the bin.