Parking at casinos just got more complex this year. Most of the properties on the Strip recently started charging to park. The MGM group of properties was first with others following. Some are even charging for valet parking which used to be free except for the valet's tip. I don't believe they've started charging at off-Strip casinos, but I suspect they've had to control Strip parking in some manner because of the new T-Mobile Arena, the big City Center area, and people park all day at MGM and take the monorail elsewhere. Every time a new building goes up, the amount of parking available declines. This, of course, affects people who want to boondock in a casino parking lot. It's simply not feasible. The off-Strip casinos are still free and many still have lots that can accommodate large vehicles. If you plan on visiting Las Vegas in your RV it would be a very good idea to call the casinos you want to visit and ask them about RV parking.
The homeless are indeed a growing problem in Las Vegas so the advice to go to a controlled-access RV park is good. If you want to see where the crime clusters occur go to the Las Vegas Metropolitan Police site at https://www.crimemapping.com/map/nv/lasvegas. By the way, Las Vegas is now a city of two million residents and it is a major tourist destination so the days of cheap buffets and free parking are disappearing.
ArdraF