We could play with examples in parallel. One is the ice cream example, perhaps another could be the following:
A Nigerian prince emails you. He promises that if you help him move his multi-million dollar fortune out of Nigeria by sending a certain sum of money by wire-transfer, he will share part of the fortune with you.
You assess the situation and decide to express value by sending the money. Then, the prince vanishes without a trace.
Was that expression of value wrong?
I suggest that it was at least less-than-ideal, or not 100% correct. In fact, I would say you've been scammed.
The alternative is to say that there's no such thing as a "better" or "worse" decision in this situation.