Why is every store asking me to take the bonus nest egg card?

Answers:
Because they can next track your buying behaviour and distribute you targetted offer, or worse, put up for sale that info to other companies that may transport you more offer.

They push the cards so you'll do your shopping here instead of somewhere else. In most stores, the clerk is individual supposed to make available the discounts to population near cards - or keytags, which are becoming completely adjectives.