You are correct to say that online casinos offers better odd than physical ones. The reason behind it is the cost: online casinos won't have the need of payment for large buildings, workers, and maintenance also, enabling them to afford to provide bettors with slightly better return to player (RTP) percentages. Land built casinos, do depend on the higher experience, the atmosphere, drinks, social settings instead on just the odds.
Therefore if you have the aim of mainly utilizing opportunities of winning, online casinos is more preferred, then when you going for the vibe and fun, physical casinos leads the way.
What you're saying isn't entirely correct. Online casinos also have staff, including programmers and web security specialists. Some online casinos even have operators who allow you to play live.
They certainly have lower costs, but not only that, it allows online casinos to offer better odds because they have a larger user base than a land-based casino.
While a casino can boast 1,000 or more users per day, a land-based casino usually operates more in the evenings, and the user base is always carefully selected.
I would even separate these two types of gambling. Online casinos are more about the game itself, and if we consider the possibility of making money, then online is definitely the more profitable option. As for land-based casinos, they are more about the atmosphere and relaxation there, besides playing, you can also just sit, have a drink, and socialize. However, in my experience, you’re likely to spend more money in a physical casino than online.