Well... it's more complicated than that. Being poor isn't a blessing. Everyone wants to make a living. In Cuba, as in other parts of the world, many Santeros/as have full time jobs doing something totally unrelated to the religion, and they don't perform services and ceremonies for other people because they don't have the time. Once in a while, when an initiation or a tambor (drumming party) is going on, a lot of helping hands are needed, so the person organizing the event will contact other Santeros/as to see if they're available to work. It is work to carry out these ceremonies, have no doubt about it. The whole house needs to be cleaned thoroughly, people have to go shopping and find food for a large crowd, someone needs to prepare the food, sometimes there are special clothes that need to be sewn, or the room has to be arranged and decorated in a specific way. Some people have to play the drums (which looks like fun, but is actually exhausting work), some people have to dance sacred dances (again, fun, but also work, it requires effort to dance for hours on end). All of these people are bringing their aché (sacred energy) into the room, and guaranteeing the participation of the Orichás they represent. There might be herbal baths and potions to prepare, which requires hours of intense work. For an initiation, which lasts a full week, there are daily chores like washing the clothes of the initiate, as well as complex ceremonies that require many participants and witnesses. People take off from work and spend the day praying, singing, carrying out rituals, doing all the things that have to be done for the initiation. For this, they get paid a derecho, which translates into money. How much? It depends on the place and the customs of the house, as well as the amount of time and work that went into the effort. But everyone gets paid a derecho, because it's not only a way to compensate them for lost time at work, but also to show gratitude for the work carried out by those who are the children of the Orichás and stand in for them at religious events. Some of the money earned as derecho always goes toward meeting the needs of the Orichás, such as adimús (food offerings), new altar cloths, new soperas (soup tureens used to house the Orichás), flowers, beaded necklaces and tools, and other gifts to keep the Orichás happy. In this way, the payment of a derecho is not so different from the collection plates that are passed in Christian churches. Observing religious traditions sometimes costs money.
Initiation into Santería is very costly because it requires the work of many people, and because many purchases have to be made during the course of the week. There are vegetables, fruits, grains, and many animals to buy - chickens, roosters, doves, ducks, goats, etc - how many depends on the individual's path in the religion and the requirements of the Orichás. The animals will be sacrificed and later eaten by the initiate and all the Santeros/as present at the ceremonies. Animals cost a lot of money, even in rural communities where people routinely raise farm animals for food consumption. If you have no experience buying farm animals, believe me, they cost more than you think. There are many other things to buy, special soap, white sheets and towels, buckets and mops for cleaning (each initiation requires a new bucket and mop, because it's a new beginning), bolts of cloth, herbs, candles, bowls. In a sense, it's almost like planning for the birth of a new child. There's a lot involved, and none of it is free. It all needs to be paid for, along with money paid to the godfather or godmother, and all the other people who work the ceremonies.
Does that mean they're doing it just for the money? Usually, no. For the most part, what they get paid doesn't come near what their time is worth. They're often working for pennies an hour, and the work can be exhausting. Clearly, most people don't do the work out of need, but out of devotion to the religion and a desire to be part of the community.
At the heart of it all, though, is the issue of respect for the Orichás. Santeros/as are the children of the Orichás and carry out services and ceremonies on their behalf. To work without payment is an offense to the Orichás, who are doing a favor for humankind by getting involved in their business. The Orichás aren't obliged to help us; they help us if they choose to. And if they choose to, we should be grateful. Orichás don't need our money, clearly. But they need us to be willing to give up something that matters to us. And, in most cases, that is something that translates into money. If we aren't willing to pay for something, how much do we value it? The cost should be enough that we feel it as a sacrifice, but not so much that it causes us economic hardship. The willingness to pay is a test of how sincere we are about wanting help from the Orichás. Since prices vary hugely from one place to another and one community to another, it's important to have everything out in the open before entering into any business with a Santero/a. It's important to know what the cost is likely to be. Although people tend to be reluctant to talk about money matters, it's possible to find out what other people have paid for similar services if you ask some discreet questions. If you've taken the time to get to know the Santero/a offering services to you, you should have a sense of how honest that person is. If you have doubts, talk to someone in the community you trust, and take your time to make up your mind before you hand over your money.