For those you wondering how people get suckered into their nonsense, similar a lot of new age 'religions' and/or cults. they purposefully go after vulnerable members of society.
Example A: Their most prominent and recruitment tactic is offering free personality tests to people on the street and tell you that you failed the test, you have serious issues etc. The idea that one can 'fail' a personality test is absurd in itself, but I digress. Once they start telling you that you have serious problems, you're more susceptible to falling for their recruitment pitch. Basic human understanding would suggest that if you're someone who would interested in doing a personality test with a stranger on the street in the first place, you're likely to be someone who is curious about yourself and/or searching for meaning in your life. And this is where the scientologists swoop in, to offer you all the answers to life - at an ever increasing price.
Example B: Scientology actually started as an alternative to psychiatry and the church has a very strong opposition to psychiatry and psychology, they love going out of their way to link psychiatry as an evil practice linked to Nazis (yes, really). They actively encourage people who have mental health conditions to stop taking their medicines, stop attending tradition therapy and so on. This one is particularly abhorrent tbh, because they will actively prey on mentally unwell people as they are extremely easy to indoctrinate and manipulate. There's been many suicides of people struggling with bipolar disorder, schizophrenia etc because they were driven to it by this cruel cult.
Example C: Similar to the point above, Scientologists actively seek out people in the midst of addictions through Narcanon (a 'treatment' programme for addictions). Again, if you are in the midst of an addiction, you are extremely vulnerable. Narcanon is not an accredited programme, it's just another load of quackery that has disastrous results. It also costs a bomb, which all goes back to Scientology. They pretend it's not a scientologist programme, but that's a lie.