Who gets to decide which cult is better than another?

I got involved inadvertently with these people many years ago in my very early 20s, all I did was buy one of their books at a street stall they had set up in London and like a twit (I have learned the error of my ways since) I obligingly gave them my name and address, oh what a mistake, they didn't let go for years and years I had constant letters and news letters all trying to recruit me to their courses (cult), I had innocently bought a book which I thought was about relieving stress, ultimately it's about relieving you of your cash, they only finally let go when I moved house and they lost track of me!