How do criminals make money on exporting Ukrainian grain?

In April this year, in consequence to protests by farmers, the import of grain and seeds from this direction was temporarily banned in the countries bordering Ukraine. Volodymyr Zelensky criticised the European restrictions, calling them unacceptable and a threat to the economy of the war-torn country. Currently, the alleged front-line countries are demanding the EU to extend this ban after 15 September this year, while declaring full approval for its transit. This triggered a violent protest from the Ukrainian side. Meanwhile, there are many indications that organized criminal groups can gain money on Ukrainian grain exports.