I'm not sure if I just can't find this information or if people exploiting government aid are just silent about it.
These things happen because there are people who are trained to exploit these situations.
But there are definitely levels to it.
One way to do it is to just start a bunch of projects that will fail in countries that cannot meet their EU funds quota.
https://cohesiondata.ec.europa.eu/overview
You look at the data here.
Figure out which EU countries can't find enough validly looking projects to get the funds.
Go to that country with some initial funding and start legitimate looking business that will be funded by EU (mostly).
Create legitimate expenses, even though the business will never be profitable and leech the EU funds through your personal accounts at some non-suspicious rate.
Involving more players makes everything look more legitimate and when things fail, it's just how capitalism works. You can spend decades leeching on the money.
On several occasions I met some fairly competent looking aliens and eventually realized this was the pattern that they wanted to exploit.
These things are also done on a personal level (for example, a psychologist wants to open a practice that will work with groups of children and the project is well-written, costs are well defined and EU gives most of the money and the person just does what they described at a lower cost - spending the money on services that will indirectly make the individual richer).
Another example is non-profits in EU. Small and large, they just suck out so much money, do the things they say will do, but the costs trickle down to the executives through various channels (for example, you can hire individuals to educate your employees but they charge you for fictional stuff and you collect the spent funds through some other way).