The amount proposed is perfectly reasonable as a donation for an occasional acquaintance & it's also not very polite to question that either.

Also, with money transfers it's partly about the principle of not losing 20% of your money when transferring from one place to another.
And it's partly about learning how to optimise transactions for future. If I didn't bother trying to minimize overseas transaction costs, I'd be several thousand pounds poorer at this stage in life.

Anyhow, at risk of breaking the mould with a reply that's trying to be helpful, reading through the banking forum at Khmer440 might be worthwhile (no promises): https://khmer440.com/chat_forum/viewforum.php?f=39