easyJet luggage charges

Has anybody else noticed that easyJet have a variable pricing for luggage? Just look at any flight and then later when the price of the flight alters so does the price of the luggage. This also happens with the price of a pre-booked seat. I think this is very sneaky and needs to be broadcast. I understand why they charge different amounts for the flight depending on how full the plane is etc. but surely luggage should be the same price whatever the flight costs?

At least I am not moaning at Ryanair as they have a fixed price for their luggage only depending on the time of the year. I am certain that if Ryanair did this it would be headlines everywhere. Just goes to show if you are the 'bad boy' on the block everyone moans but if you are the 'good boy' then it is not spoken about.