Above, dear friends, is a Nectar Card on which you can claim points for purchases at Sainsbury's and other selected retail outlets, not including Boots.
Meanwhile, below, you can see a Boots Advantage Card on which you can claim points for purchases at Boots. And only Boots.
This means you cannot use a Boots Advantage Card to claim points on purchases at Sainbury's.
First thing this morning, I stopped off at Sainbury's to buy a packet of these.
Upon swiping them through the self-service check-out, I mistakenly tried to claim the points (not many points, considering the biscuits were on offer for £1) on my Boots Advantage Card. I was wearing a pair of these at the time and therefore not concentrating properly.
The fact that I was wearing these, with cheesy tunes blasting through them, made it impossible for me to hear the nice Sainbury's lady attempting to point out my error. Their presence in my ears also made me unaware of just how loudly I was swearing, thereby attracting her attention in the first place.
So, the moral of the story is, don't try to use your Boots Advantage Card to claim points for buying chocolate biscuits in Sainsbury's. Because you can't, even if you didn't mean to.
I hope that information is useful.