Such a request will ensure that such people will have difficulty in getting us interested in them. Saying a prayer does not however ensure that we will never make an error in judgement. Fortunately, cults have certain characteristics that make make it easier for people to spot them. This is generally because they are concerned that people may find out that they are being deceived in some way. Their other concern is that by being asked questions people may find out how little they really know.
People knowing about such things make life much more difficult for cults.
This, of course, is untrue. Spiritual growth comes from our own doing. The difference being due to difference in worth of the subject matter, the presenter, the venue etc. Be careful if activities etc. are at the high end of this scale or are even more expensive. They prefer people to only believe what they are teaching.