Guys, why you neeed to hide BIP38 key? Or even trust me to destroy those keys?
You'll give me ONLY encrypted key and only you will know pass-phrase.
I propose to all backer on Kickstarter to use this site:
https://walletgenerator.net and generate there BIP38 protected keys. And for sure don't tell me that pass phrase.
The only thing you need to trust me is that I'll make engravings on metal cards

But that will be a really bad idea to bury a successful kickstarter account for extra several hundreds dollars.
I do understand that there is no need to hide or destroy the privkey but when it comes to my BIP38 keys i only keep the passphrase for them at one place - my mind. I don't want to forget it, lets say in 5 years- so i keep them short at 10-20 characters.
I just think, having a cover for the privkey would be extra security