Sounds like the employees were let go for dishonestly abusing a perk. It's hard to tell from the linked article but I presume you get these meal vouchers if you are working early/late and are in the office during meal times. These bad apples were using the vouchers to have food delivered to their homes while not working, or buying non-food items. It's a clear abuse of the policy and hard to understand why someone making such a good salary would risk it for peanuts - but many of my high-earning friends are also some of the cheapest people I have ever met.