Who said they were planning on it? The real economic implications of that scale of payout are basically unknowable.
Contrary to pithy internet comments, cash windfalls have been shown to unlock the economic potential of that money very efficiently. Replacing food aid with one-time direct cash aid leads to higher quality of life for the poor. They actually do invest it in housing repair, transportation for jobs, necessary clothing, etc...
Yeah some people are just gonna do $400k worth of cocaine, but the myopic view of a stereotype lottery winner is pretty unfounded.