In my company (Fortune 500), we get new notebooks every 3 years and IT persistently pesters owners of old notebooks to return them. Given the sheer number of devices, I can imagine a reselling contract to be a nice additional source of income.

In this company's case the PCs were the cheapest of the cheap. Bottom end Dell and HP stuff.

when they were life expired they were given over to a recycling company, whom I assume would take the time to pick the epoxy out of the USB sockets or probably just replace them. I think buying new USB sockets and connecting ribbons to the motherboards is probably quite cheap these days

In the US, above a certain size you're basically required to sell off the old hardware because throwing it away counts as polluting, and the people who dispose of exclusively tech stuff charge you for that service.

Yep, look on eBay for sellers that specialize in refurbishing them. It's a great way to get something like an older Thinkpad for really cheap. Perfect for a Linux laptop that doesn't need the latest and greatest.