Nearly 10,000 tons of corn were stolen from the grain depot. How was it stolen? Why did the grain dealer only give 50,000 to the warehouse clerk when he made a profit of 25 million?

According to news on April 22, nearly 10,000 tons of corn disappeared from a grain depot in Hebei over the past two years. Grain dealers colluded with the warehouse staff to steal and sell the grain and make a profit of more than 25 million yuan.
If each person eats 1 kilogram of grain per day, 10,000 tons of grain can meet the needs of 4 million people for 5 days. However, the police in Qinhuangdao, Hebei received a report that nearly 10,000 tons of corn "missed" from a grain depot between 2020 and 2022.
The police investigation found that the grain dealers colluded with the warehouse staff to manipulate grain trucks when they entered the warehouse, registering more than one truck and falsely entering the warehouse; Leaving the treasury without authorization and obtaining a large amount of funds. After investigation, the grain merchants made a profit of more than 25 million yuan from selling grain, and the warehouse staff received 50,000 yuan in benefits, and three people received "wages" ranging from several thousand to 10,000 yuan per month. Currently, several persons involved are suspected of contract fraud and theft and have been transferred to the Procuratorate for review and prosecution.