If you want to make people recycle their rubbish, then collect that rubbish as recycling. Given that the polystyrene foam of a takeaway tray *can't* be recycled (or at least, no councils that I know of will collect it) you are penalising people for throwing away something that they have no option but to throw away (apart from hoarding it!) because there is no alternative.
We recycle everything that we can (cans, bottles, paper/card) but we still find that some weeks our bin is full to the brim with things that we can't recycle, and we have to keep the last couple of days' rubbish another fortnight until the next collection. "Recycle more" is an excellent sentiment, but "produce less waste" is unrealistic if the waste can't be disposed of any other way (eg as recycling).