I thought a wall socket was only good for 32 Amps? I don't know for sure myself, i'm still learning. I read it on the forum somewhere.
Some sockets? I guess??
You can easily draw over 2000 amperes from a typical outlet... it's just a question of, for how long. At that rate, the breaker will trip within a cycle (< 10ms). Which, mind you, is an electrical eternity -- say a transistor was dropping that voltage (even while drawing far less current -- transistors can't draw fault current, but a fault condition like SMPS shoot-through, or driving a shorted load, will still quickly be fatal), it will die in about 20us. So the breaker opens after about 500 transistor deaths, by which time the one transistor has thoroughly turned into an expanding plasma ball.

Over longer time scales, you want to keep the RMS current below the fuse/breaker rating (whatever that happens to be -- and for UK circuits, I believe that includes a fused plug and cord, versus the US system that assumes any outlet may be asked to deliver full rated current). RMS is an averaging process, so the peak current can still be much more than rated -- again, it's just a question of, for how long.

In the present case, blowing a ceramic cap will have an equivalent RLC circuit, which will peak at around 1.5A in 3.5us, then 680V at 7us (worst case, switching at the instant of maximum line voltage, and assuming mains inductance ~500uH and capacitance 0.01uF constant). In practice, the ceramic's capacitance will drop off rapidly as voltage rises, so the peak current will be lower, and the peak voltage will be far higher, probably over 1kV. At that point, the LR8 is guaranteed to be unhappy; it may well happen that it can bear modest avalanche currents (<1A in this case), but it may also be gradually damaged in the process. Of course if the capacitor fails internally, you don't get a chance to see if that happened...

Tim