Oh yeah, I'm not so much condoning the price increases, but I don't know why anyone expected different. £30 for an arrow 4k steelbook with a booklet is "normal", and offers miles better value than disney/mcu 4k steels for the same/more money. Studiocanal charge £30 for anniversary 4k steel releases with 3 discs as well, which i also consider relatively good value.
Even arrow's basic blurays are much more expensive than the price other studios typically set their 1080p releases. The value is brought with the pure effort they put in to the collection of features, sleeve art and booklet. Their 4k releases are the same, a good £5 more than the £20 standard for catalogue titles, which is comparable to their 1080p prices.
Yes I used discount and free delivery, but £35 for a x2 disc 4k steel with a hard slip, 60p booklet, x2 posters and x7 cards offers tremendous value. Of course only if your interested in all that