The debate is framed as "$5 a day is a waste--put it into your piggy bank every day and drink office sludge instead".
I instead say that yes, the office coffee still tastes like fertilizer, but I still think $5 a day for a latte is waste because I can make some excellent coffee at my desk for about a dollar a day using an inexpensive French Press, a hand-grinder (or grinding the beans that morning at home), and some whole beans from your favorite hipster coffee shop. And the 5 minutes it takes start-to-finish (1 minute for prep, 4 minutes for steeping) is probably less time than it will take to slip by the coffee shop, stand in line, and get your order.
But that's just me. If they're one of those people who uses the coffee/espresso/latte as a caffeine-delivery mechanism and rely on being a frozen whipped-cream confection with chocolate and a little coffee in it to make it palatable, then my self-brew method won't help them.