Proscribed fun is hard. I can think of about 20 great engineers who would be turned off by a scotch library and free trips to the driving range (is it software for country clubs?) Substitute any of foosball, ping-pong, beer kegs, red-bull, razor scooters and whatnot. You're only going to please half the people, half the time, and probably the wrong people, because who really ever liked razor scooters and nerf guns, a…
One thing we try to do is to run internal classes. We had one on C programming that I need to get back up and running; we have a long-running one with cryptography.
Businesses routinely do the equivalent of paying a grad student to teach machine learning; they just don't call it that. In the real world that's called consulting.