and if people always lost, vegas would collapse because people would stop going.
You could make the argument that any other expensive hobby is also throwing away money:
* boating: buy a brand new boat for $65k, sell it 8 years later for $35k, plus $5k in total operating costs/insurance. You just "lost" 35k (not counting interest)
* rock climbing: buy $3k of gear and travel, $2k on lessons. Fall and break your arm for $6k, $11k "lost" for a couple years of entertainment.
* "travel", spend $6-10k on hotel, airfare, meals, in 2 weeks, all we have left to show for it is "memories". Great "investment".
(disclaimer: I'm not actually against the things I just mentioned. Only pointing out that they are "throwing away money" just like a weekend in vegas). Unless you're some hyper-disciplined monk who only uses money for humble necessities, you, too are throwing away money just like people do in a casino.