The purpose of faucet is marketing
just anyone sit down and do calculations: how much does someone earn with facucet? the person earns little and is earning in a casino and taking the same money to play in the casino, the casino is not earning any profit with that, I don't even know why casinos do such a thing, because they don't make a profit with that kind of thing,
Like the post you quoted said, that's all the purpose of faucet, they act as a form of marketing/promotion.
You can agree with me that lots of people like free things, most especially newbies, I was their so I am telling you this from my personal experience, I have joined many casinos in the past namely Freebitco, BC.game and many others I can't remember their names for the sole purpose of earning free crypto, and I eventually ended up depositing money and playing and losing everything on those casinos respectively, that is the casino make profit from faucets, I can tell you categorically that if not for the faucets on those casinos I mentioned, I never would have had any account there.
So faucet is indeed a good marketing strategy casino use to win potential customers overs, at the beginning, it might seem the casino is not making profit from that, but in the long run, more than 50 percent of those who joined the casino because of the faucet would eventually deposit money, play and lose it all, so it's always a win for the casino.