The problem is he was looking for your weak point and it sounds like he found it. Block and ignore would my advice. Don't let narrow minded ruin your day.
It's a Grey area...you can till there is a complaint about it then it is a violation of your visa. Do you want to chance your visa over helping out at a wat. Crazy yes but it is Thai law.
As with many scams..it all comes down to money. They pray on many who are unprepared or are ill-informed or trying to get a great deal for a cheap price. Buyer beware.
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