I have seen this happen, first hand, in the public sector. I used to work with two guys in a company that shall remain nameless. After a while, they started tak

I have seen this happen, first hand, in the public sector. I used to work with two guys in a company that shall remain nameless. After a while, they started taking some of the team to lunch every Friday. Not a quick, frugal lunch, but lunch at some nice restaurant downtown, with lots of food and drinks, taking a couple of hours. And they would sign for those lunches all the time, as company-approved expenses. After a while, having become a bit closer with them, they confessed to how they did it: they had found a bug in the company's control system, where each of them could approve the other guy's expenses. So they would take turns signing off their lunches; after a while, they felt confident enough to invite other people to them. I stopped working with them soon after that, but I heard they kept up this act for quite a while.