Hardware vendors could chose to, for example, make the keys available in printed form in an envelope with difficult to open without breaking vendor-branded seals that are expensive to manufacture in small quantities, and warn consumers not to open them if they don't know what they're doing.

This would prevent its use to lock consumers out from installing their own software on their own hardware, while still making it useful for legitimate applications. Consumers could chose to securely destroy the key if they wanted (with the caveat they could then not on-sell the device).