My aunt was a medium. She certainly believed in her gift and so did others, although my dad (her brother) was a sceptic. She was attached to a spiritualist church and wasn't paid for her work. She believed that it was her duty to act as a channel between the spiritual and the material world.
The question of money always arises when spiritualism is mentioned. Obviously, if someone is a leech and latches onto a bereaved person with the intention of bleeding them dry, that's contemptible. However, if modest sums are involved, is it any different to giving money to the established religions? After all, they also claim to meet people's spiritual needs.
I went to two funerals, a couple of years ago. One was Christian, for my next door neighbour. It was obvious that the minister knew nothing about him and just waffled about him being "a lovely gentleman." (He wasn't.) We had two prayers and two mumbled hymns, and I found it hard to believe that his widow found much comfort in the whole thing. The buffet and the chat in the local pub, after the service, probably did her more good. The minister, of course, would have been paid.
The second was Hindu, for my FIL. The priests have got the whole thing off to a fine art. There's a lengthy funeral ceremony, a ceremony to release the soul, a ceremony to dispose of the ashes and an anniversary ceremony a year later. Of course, there's a fee for the priest every time. Part of the funeral was in Sanskrit, which nobody except the priest understood, and he gave a rambling talk about life and death which he seemed to be making up as he went along. Any comfort that my in-laws felt was clearly derived from knowing that they had correctly performed the ceremonies which the priesthood had invented in the first place.
In both cases, the religious leader was paid for providing a spiritual service. There was not much comfort beyond a vague hope of meeting again in heaven or in another incarnation. I am not surprised that people are prepared to pay for a message that their loved one is okay. And if they go to a spiritualist church they have a good chance of getting a message for no more than a contribution to the collection.
It might be made up but that applies to all religion.