Whilst I quite understand your point, I have to pass some of the blame towards the publishing industry. These days, in excess of 70% of newly published titles we select for addition to stock are being published in paperback, making paperbacks by far the majority format. I know for a fact that publishers are now only likely to produce hardbacks where they are guaranteed a large number of sales, and therefore the shift to the volume of paperback publishing is only going to increase.
For this reason, we cannot sustain separate collections within our libraries for the two formats, short of offering an organised arrangement of sturdy books on shelves, and a chaotic collection of variously sized paperbacks on spinners. I'm sure you can appreciate this creates additional problems for those customers who are looking for particular titles or authors.
So the shift in all 36 West Sussex libraries will be towards interfiling hard- and paperbacks alike, into sequences favoured by the borrowing public (for instance, separate sequences for crime and thriller books), and leaving the promotion of the newest and most popular titles through displays on standalone units or face-on display.
I appreciate this doesn't give you the answer you may have hoped for, but I hope it does go some way in explaining the reasons behind what is happening.