The 'disaster relief' work is indeed a money maker for the WT.
One comment I would add that hasn't been mentioned yet regarding flood damage, particularly in light of recent news of flooding in parts of Kentucky (US). Homeowner insurance in the US does not cover flood damage. Flood insurance in the US is the federal Flood Insurance Program. Homes that are not in a designated flood plain are seldom covered by the flood insurance unless the homeowner has voluntarily purchased it (relatively rarely so). The poor folks in KY mining towns situated along rivers nearly all are not covered for flood insurance. I don't expect the WT will be organizing disaster relief for the recent KY flooding, as there is no money in it for them.