House edge is there to protect the interest of the house much more than the interest of the gambler this is so that gamblers stand the chance to only win the amount that their luck permits them to win and most times, one needs to look out for ways to prepare your mind that winning in gambling only occurs via luck and nothing else so while gambling never expects a winning.
Without house edge, this business can
't survive. Without it, I believe, a lot of casinos are already in the bankruptcy stage especially if there are huge amount of winnings.
Hence, establishing the house edge in a casino business is actually important because that's their bread and butter so to speak in this business. This will dictate their survival chance in this type of business.
From time to time, there are definitely some winning bets. However, in the long run, there will be more on the losing side. Hence, casinos are considered to be one of the lucrative industries because they can generate good income. Do remember that during the pandemic days, online gambling was one of the few businesses that thrive and can still offer some monetary needs to the government.