Lottery tickets are almost always negative expected value which means you're basically lighting money on fire, and governments worldwide love them. More generally the US government acts as an oligarchy. Government self interest, followed by special interests are what generally drive government action. Public utility (and opinion) play a very minor role. And yes, I even have a source for this as well as I understand this is not what many people want to believe. [3]
[1] - https://www.fool.com/investing/2016/09/25/how-much-does-the-...
[2] - http://news.gallup.com/poll/193874/half-americans-play-state...
[3] - http://www.princeton.edu/~mgilens/Gilens%20homepage%20materi...
However, around 64% of Americans own their home [1]. How many of them are taking out HELOCs against their homes to buy lottery tickets? Once concern is people are taking out HELOCs for crypto speculation.
[1] https://en.wikipedia.org/wiki/Home-ownership_in_the_United_S...
Homeowner is not the right term for most of that 64%, because most have a mortgage balance, which when subtracted from their < $1,000 in savings, makes the picture even uglier, and makes most of their future financial well-being dependent and correlated with their local real estate market.
Edit: The stat actually means 64% of homes are occupied by their owner. But "owner" is still misleading, as the article linked to above says:
"However, homeowner equity has fallen steadily since World War II and is now less than 50% of the value of homes on average."
Because to me it should be easy to understand that Lottery isn't marketed/treated as an investment (crypto has started to be legitimately treated as such), and historical returns don't suggest it would work.
Crypto is just attractive enough it could pull the wrong type of attention from everyday people acting as investors.
I don't agree with direct regulation, but I can definitely see why the government would be worried.