I think how you feel about this often depends a lot on how you travel there.
Packing a box with a few bits from home is easy enough. Likewise, buying a box of dishwasher tabs is no biggy if you can just take the rest home with you. But I don't have a car, so I've travelled by train. I don't want to spend 4€ to run the dishwasher twice over a long weekend when I'm already paying enough for use of the place. If it's not already there, chances are you're actively removing it between guests and I very much resent being forced to stock your house.
So adequate quantities of all powders and tabs necessary to run whatever appliances you've got (dishwasher, washing machine).
Cling film/tin foil
Plenty of bin bags and very clear instructions about how to sort recycling and where it all needs to go. (As PP said, not via the tip on the way home either.)
Basic kitchen supplies: oil, tea bags, proper coffee (and filters if necessary - that one was infuriating), instant coffee, sugar, salt, pepper, sweeteners.
Butter dish and tea pot with cosy. Very pleased to find these.
No fresh stuff. I'll feel obligated to use it, which is potentially inconvenient. I have previously left a place carrying half a homebaked cake because that felt less awkward than leaving it abandoned on the kitchen table.
More than one dish cloth and tea towel.
A washing up brush and scouring pad.
A potato masher. (Not vital, but a real bummer when you suddenly realise there isn't one and you'd assumed there would be.)
Access to Hoover and basic cleaning supplies (this does everyone a favour and i will spill coffee or sugar.)
Hand soap (liquid, so I can also use it in place of the shower gel I've forgotten and so it doesn't have to be new every time).
Loo roll. Plenty of loo roll. (Stayed in a place once where they left us only one. We ran out on the Sunday when all the shops were closed - we were actually working and crazy busy, so hadn't been paying attention - asked the owners, who lived next door, if they could let us have another and they said no!)
The latest check out time you can possibly offer and somewhere you can let us leave our luggage for the day if you need us out by 10 am, but our train doesn't leave till the afternoon.