They probably already have people drying their dishes. My sister gave me a “tea towel”; I was not thrilled.
I would send a flower arrangement after I left.
I agree with CottonTales—order from Wolfermans to arrive just before you arrive.
Their English muffins are amazing and helps with breakfast.
^^ Along those lines I thought also of something that could aid in entertaining food wise that weekend. Like the Wolfermans or some cheeses (to go with the delicious wine they may offer!) You could send it ahead of time with a note saying “looking forward to meeting you both and discussing the upcoming wedding!”