But they can grab past years of data, not just what you are spending now. The only way I'd use this nectar offer is to start with a fresh credit card and use it for nothing else.
I know how it works. I don't mind sharing my spending data in exchange for some free points. Not to everyone's tastes I appreciate
They can get all your card transactions, not just ones for nectar partners according to the terms and conditions. Noped right out of it. I don't mind Nectar building a profile about me on shopping I choose to collect points for but a blanket snooping of my bank account is way too much.
You need to learn to read the smallprint more by the sounds of it.
Hardly random is it, its a well known supermarket. No different to using Experian Boost imho