They had previously conducted business via text message, the business deal had been discussed previously and when asked for confirmation that the deal was good via a picture of the actual contract the farmer responded with a thumbs up. The buyer then had to purchase the goods at the current market rate that was significantly higher which put him out of pocket.

So the guy suing the farmer could show that not only was this a normal way of them doing business, but he had effectively written acceptance of the deal (the emoji) and incurred a substantial monetary loss as a result of the agreement not being honored.