Can you write down prices in shops?

This article from the Guardian really interested me after a bad experience I had in Currys in Shirey (West Midlands).

Guardian journalist almost arrested for writing down prices in Tesco

Although after reading more about this Tesco have apparently not passed a new law prohibiting the writing down of prices in their stores.

So what was my experience ....

Recently I went into Currys to buy a piece of hardware for my son's computer. Wanting to get a good price I scanned it with my phone to use a comparison app. I was practically jumped on by a member of staff who said: quote "that is stealing". Forgive me for being thick but I really don't see how scanning a barcode can possibly be considered stealing!

Perhaps this is the new economic climate where you can't go into a shop, scan bar codes and then look elsewhere.

I really want to go to Tesco with a notepad.