The Royal Parks Agency aren't the first organisation to try to ask the public 'please take your litter home with you'; those infuriatingly moronic station platform drones that warn you that your luggage may be damaged or destroyed by the security service also ask the same thing. The result is invariably similar, as anyone with an ounce of nous could predict; people are reminded to jettison immediately whatever rubbish they have around their person.
Look, the deal is simple. When we're out, we'll buy ice creams and burgers from your astonishingly overpriced franchises; we'll spend a fortune on cardboard containers that purport to contain coffee, we'll buy newspapers and magazines from your concession stands. All we ask in return is that you provide a sufficient number of large capacity rubbish receptacles around the place for us to dump the waste in. You must be either stupid or naive in the extreme to imagine that we're going to cart a festering putrescent burger wrapper all the way home to dispose of in our own over-regulated, prodnose monitored wheely bin.
The Royal Parks Agency may be 'disgusted' that park users didn't take their rubbish home at the weekend. Park users, I suspect, are equally disgusted that the RPA didn't provide skips at all the park entrances for them to leave their rubbish in. As usual, it all comes down to the EU and their myopic and counterfactual policy on landfill. The answer to both the Royal Parks and rail companies fiscal costs is the withdrawal of the UK from the EU, not to transfer the costs of refuse disposal to householders and councils.