My experience was they used them to bribe you to a book study. Only the study conductors gave them out to make sure you were active. I was refused one at a watchtower study, told I needed to go to book study as that was Jehovah's arraingement.They would not let my husband bring one home , only BS conductor could witness it. I was no longer attending BS due to cognative disonance induced athsma, but still in good standing.
CONTROL , CONTROL, CONTROL, their excuse was to weed out weak ones who might carry the card then backslide & give a bad witness by taking blood. Lack of attendence = lack of faith.
This was just one of their reasonings that got me out.
Disfellowshipping was a relief and cure for athsma, too.
Blithe
Blithe