Changing the rules once they have you hooked

I noticed an email from Big W about everyday rewards cards where they are changing the amount of points you receive.
Normally you get 1 point (qantas) for every $1 above $30...You will still get it if you shop online, but if you shop instore its 1 point every $2 over $30..so effectively halving...
They are trying to change peoples shopping habits, and eventually cut down on physical presence . Same with woolworths there are heaps of incentives to shop for groceries online...the longer term trend is less staff in store and less supermarkets..
Did woolworths recently spin off their buildings to a different entity? could be a clue why