Unfortunately Tesco's loyalty scheme requires an app, which is far more invasive than knowing I regularly buy cat food at Sainsburys. So I have a Nectar card but not the Tesco app.
I have a Tesco Clubcard (physical card) but not the Tesco app...
Last time I asked for a clubcard they said the only option was to use the app. According the website you can still order a card after registration though. Meh. They're really pushing the app these days.
I found one on the floor. I use that one now.
still getting by with the little plastic tesco barcode card on my key ring.
But it's just a matter of time, before I'll need all the apps on my phone.