I hope this question hasn't been answered elsewhere - I have tried to check...

I always try to fly in an exit aisle seat - probably 95% of KL flights, because I'm happy to pay when I book.

KLM cabin crew are very active in briefing pax about the exit row - which is a Good Thing. However... they are sometimes, IMHO, over-zealous in telling the exit row pax that they must put away their books/newspapers for take-off and landing. We all have to just sit there. It happens on roughly 1 in 10 flights, I would guess.

Is this KLM SOP? If it is, why is it (relatively) rare? If it's not SOP - and I assume it isn't - why do they do this?

Input appreciated, thanks.