Personally I think the guy is a moron. If he wasn't banging his head so hard he might realize it's reasonably priced and he can save all the corporate hassle by purchasing it himself.
Enterprise doesn't work that way. There are a lot of situations where you aren't even allowed to use free-as-in-beer open source software due to security and/or other concerns, let alone software that you've paid for yourself. Besides, if the company is the one getting the benefit from the usage of the tool, why should he be the one paying for it?
The way where I work works (technically enterprise, a couple thousand full-time employees), if you want some software and think it's reasonably-priced, you can buy it and expense it. I've never heard of anyone getting in any trouble over this. You can also submit a helpdesk ticket to have purchasing buy something for you, which is what we'd do for e.g. Subscription licenses which require someone entering a corporate card and keeping track of it.