The etiquette with the offering cloth is this: if a female is offering food, clothing or medicine to a monk, he will lay a cloth/bowl or other suitable item in front of him. The lady puts the item on the cloth and it is then ‘offered’ – which means it has formally been given to the Sangha of monks. And of course vice versa between nuns and laymen.
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Things are ‘offered’ in this way so there is no discrepancy between what has been given to the monk and what has not – so that he does not take something on presumption, that the owner might not feel is appropriate. If a layperson touches the offered item after this point, it is then considered ‘unoffered’ and the monk will not take it for his own use.
The post ends with a discussion of cultural traditions and attitudes (namely attitudes towards others’ cultures). It’s certainly nice to discover that some of the customs I’ve witnessed (such as the “drop method”) are not merely idiosyncratic customs of particular monks I know.