Do They Think I'm Stupid?

One of the credit cards I use regularly is my Discover Card. I like their Cashback Bonus. One of the things I like about it is the ability to get my $20 cash bonus as a gift card worth more than $20. One offer they have is to get a $25 Red Lobster/Olive Garden gift card for $20 worth of cash bonuses, but that's not all, they also offer a $45 card for $40 in bonuses. Maybe some people would go for that, but only people who can't do simple arithmetic. Why not get 2 $25 gift cards for $20 each?