Why doesn't Waterstones (UK BookStore) also upsell kindle books?

Today I bought a book for my Mum in an local Waterstones and they didn’t even have the option or service to upsell a digital copy of that book!

If they had an offer like “25% extra and you also get a kindle version” I would had bought, because I also want to read that book (and they sell Kindle’s in that store!!!).

No wonder they are struggling (see Waterstones boss pledges to revive company's fortunes after a £37m loss  ), and although Waterstone’s management wants to blame Amazon (see Amazon is 'destroying Britain's book industry', claims Waterstones chief), they keep failing to adapt to the new digital world.