If you’re rolling D20s, but there are also D4s, D6s, D8s, D10s, D12s, and a D10 Percentage die for 5e, and some spells require multiple of the same dice, so rolling 6d6 is a very real scenario, so you can have plenty of dice to use to find variations to get to 7 with different sided dice.
Don’t worry, there are dice in (at least some) prisons, every cell block had at least one D&D group going with 4-6 people, and they used dice.
Source: Was a prison guard in the ARMY for 4 years at Fort Lewis.
This goes back even further, Randall is referencing the ps3 security, that has a constant instead of a random number. That allowed failOverflow to remove one variable and reverse the private key to sign ps3 apps.
Yeah, no doubt different facilities run things differently. Depends on where you are, who governs it and it’s security level. Low security gets more privileges than medium, high, or maximum security. Though for us medium security and lower could have small games, dice, dominoes, etc during rec hours.