The difference is that PSN and XBL don't know that you already own the games, so it's sold as a new game purchase and it's left to the purchaser to decide whether the convenience of the format-shifting justifies the price.
In this case, Sony know categorically and beyond doubt that you do indeed own it already, and is setting the price for people who already own it. If it was an invariant £1 token fee, that would be one thing, but £19 as a reissue fee is preposterous.
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The difference is that PSN and XBL don't know that you already own the games, so it's sold as a new game purchase and it's left to the purchaser to decide whether the convenience of the format-shifting justifies the price.
In this case, Sony know categorically and beyond doubt that you do indeed own it already, and is setting the price for people who already own it. If it was an invariant £1 token fee, that would be one thing, but £19 as a reissue fee is preposterous.