Possessing random data is also a crime since it's indistinguishable from encrypted data, and if you can't provide the non-existent keys, your SOL.
You really shouldn't be able to access /dev/urandum until you have been cleared by a reputable Alphabet company. This is for our security and that "obviously" trumps individual rights (whatever that means).
Root cause of all this is, of course, "bad thoughts" and "bad information", which IMHO should also be made illegal and only permitted in designated "free and error prone thought" areas and participants monitored by physicians from the Ministry of Error Free Thought.
You have no idea if a file contains something needed as part of a decryption process, or if the file itself contains encrypted informations.
So basically, having a "pad" file incriminate you.
Plausible deniability by allowing you to decrypt with one of two different passwords. One gives you access to the volume with your data, the other opens a shadow volume that contains random non-senstive data.