For nation-state clients
The product wasn't plug and play for the nation-state market wishing to spy on any and all HTTPS traffic crossing the borders.
By obtaining the trusted intermediate cert. the product has become plug and play for the likes of Syria, China, USA, Russia, UK, N.Korea, Australia, Denmark, or just about any country you can think of to spy on their citizens' and each others' citizens' HTTPS traffic.
It also makes it easier for the existing clients by not having to install an extra cert. in all the browsers for the appliance to work.
Democratized trust certificate model, sounds like how PGP was setup.