There are some ways to earn money without paicing bets and I would like to talk about some of them.
First and the main one is the affiliate/referal programas, this way by sharing your affiliate link you will get some incom from the users bets, isn't easy to get good affiliate (users who bet a lot) but with one high roller you could make a descent amount.
The second one is the VIP programas, like the one that stake offers, you need to bet to grow your account, but once you have a good VIP level you will get a weekly and monthly prizes, It will be better if you bet that month but even without betting you will get something each week/month.
None of this two things you mentioned are feasible or dependable when it comes to earning or making money off casinos actually placing any bets and or gambling.
The first one you said is sharing referral links, this is not something any one would want to dable into except the person is an influencer and has a very good level or number of followers, else, it is as good as impossible to make any money from casinos this way.
Second you mentioned was gambling until one reaches the vip level in the casino, this one will require the gambler to first spend a lot of money first, this completely defeats what is being discussed on this thread.
The conclusion is, there is really no dependable way of making money off casino without first spending money.