Strangely, rockets aren't the only types of attacks that crit!!!!!11111
There are a number of weapons that aren't powerful enough to kill 125 HP classes in two hits, but they will in a single crit shot, because crit shots do triple damage and ignore distance damage falloff.
Edit: My bad, it's only melee crits that do triple damage. Normal crits do double.
And clearly it doesn't matter to you that much or you would have noticed that BLU has had random crits off for the last 4-5 weeks... well before the last major update where they removed the nocrit affect from a number of weapons.
Which just goes to show what Necro said is true: If you just turn random crits off, no one will notice... other than the people who play Spy a lot, because the backstab animation doesn't play any more.
And before you ask, random crits are still on on RED.