It is a bit of con but most manufacturers seem to consider this within tolerance. The consumer however sees it otherwise.
Take it back to the shop and simply state the dead pixel is in such a location that it make the screen unuseable for you, is thus unfit for purpose and demand a refund / replacement. Given that most major retailers have no quibble refund policies these days, and online retailers have similar policies then getting it changed shouldn't be an issue. Stand up for your rights
