I am almost certainly overthinking this...
We got a thank you card for a present we bought from a gift list today. The wedding isn't for a couple of weeks. I know that we should just be grateful for getting a thank you card given how many people seem not to get them. But I do find it odd to have been sent it before the event. Maybe I am just envious as I didn't think of doing this before our wedding and had a pile of cards to write afterwards. On the other hand it was good to be able to thank people for coming and say how lovely it was to see them.