Sure, but they’re still potentially sitting in limbo and turned off in the trunk of an employee’s car or whatever. If you’re concerned about leak issues, why not wipe them and have them shipped back for less than the cost of an extra week of severance.

Also, many employees likely have their own personal laptops and may not have any use for them.

In my experience, so many people these days do not have personal computer at home. Their personal computing is phone/tablet and if they game, it's done via a console.

EDIT: My wife didn't until she got "second job" as volunteer and needed to do some real work. Before that, she was planning entire vacations from her phone.