What would the cost of a coffee vending machine be? That said if you can get a good one then I would say yes it would solve your problem when it comes to the time it takes to make the coffee and they will no longer be able take small amounts home but sugar might still be a problem.

That said they will start spending more time visiting the toilets. "It is just how these things go…"

I recommend setting up a policy for coffee breaks and the like and set out some clear rules regarding the problem. Then install a small security camera and keep an eye on who is spending too much time taking breaks and also see if you can find who is nicking the coffee.

The vending machine will probably break down a lot… "The one we had was junk, it made horrible coffee AND it hardly ever worked properly" That said if you can get a good one why not try it?