This reminds me of something I always thought was interesting. Black Friday is the big shopping day after Thanksgiving in the United States.
They've always told everyone that it is called that because it is the first time many of the stores manage to get themselves into "the black" as in, no longer with money in the red.
Actually it was originally called that because the shopping hoards created such disruption for traffic that it was considered a real annoyance.
The shops liked the more positive view and so they always say the name came from there and who can blame them.