I like the one who suggested the answer to the question of how much the free drinks cost should be "less than the cost of hiring a single engineer".

Used to work at an office where they got rid of free drinks. The morning it happened, Top Engineer 1 sent a mail to all Boston staff announcing he was thirsty and asked if anyone else was similarly thirsty and wanted to join him on a grocery trip to buy soda. Three cars full of engineers went to the grocery store, taking a little over an hour. Free drinks returned later that same week.

Right, the whole point of free food/drinks was the keep the engineer from wanting to leave the office. It was not really a perk but a way to entice the employee to working more.

This exact event happened at both Cisco and Juniper when they got rid of free drinks. Multiple times.

I love that guy.