It's their only way to recover their economy and nothing more. Even in other countries, they did the same as they already started to open casinos to save their economy. They just implement a protocol to at least prevent the spread of the virus, like social distancing and sanitation, etc.
True, so far I haven't read any news blaming the Las Vegas Casinos for opening their business, most of what I read are just all speculation, people saying the popular "what if" words, but they didn't realize the contribution of this opening to the economy. The government knows betters so they would not approve it if it's not good for the majority of people, maybe not on the entertainment side but on the tax the government will collect.