When I move out, the first thing I do is call the PoCo to end my service. I suspect the power was already "off."
The second possibility is that the bomb simply didn't work, and the sparky found it when he began troubleshooting the light. Bombs are not nearly as easy to make as "The Anarchists' Cookbook" leads you to believe. I've seen countless 'never-fail' recipes fail to perform.
For that matter, electric work isn't as simple as it seems. Anyone want to guess that the connected wires were of the same potential?
