I "love" how the reward are gift cards, not actual money. How much more insulting can they be: your privacy is not even worth liquid currency. Some people probably need the gift cards, but it's as upsetting as people selling blood for gift cards.
some people have different value judgements than you do -> those people also probably think statements like yours are paternalistic and condescending.
I think most people would prefer that to receiving a check in the mail, or cash in the mail, or supplying banking details for a direct deposit.
They seem to have cards available for multiple merchants. If they have a decent selection there should be something available from a merchant a given subject actually buys things from. If so, a gift card is pretty much as good as cash.