We've had this challenge as well at a smaller scale. People would go out to lunch all the time to "discuss work" and expense it. We were paying thousands a month for that.

After a while that, and a few other things, got a bit out of hand.

Rather than just go after that, we've made it a goal (among other quarterly goals) for everyone to work towards a certain amount of profitability that people can have a part of.

In addition to reducing expenses (yes, it's cheaper) it's also created a bit more of a frugal culture in the company. It's great, people watch what they spend themselves and are much more concerned about their departments' budgets.

Mind you, we have less than 30 employees at the company (I'm one of the founders).

Also, all expenses automatically go to your manager and then get reconciled by our accountant who basically has OCD and will question anything that even looks remotely questionable to anyone including management.

Point is, we created this more frugal culture so everyone can have a bit more in the long run.