That matters why? Do you question and complain to your friends and loved ones if their gifts to you don't fit according to their income?
Too many people in the world that don't understand what a gift is and have false impressions on how they think they HAVE to be treated. Nobody owes you anything, not a Christmas bonus, not a t shirt, not a gift card. Apple employees accepted employment where they did and unless it is stated in a contract, they are guaranteed nothing more than their salary and basic employment rights. There are millions of people in the world that are unemployed, recently laid off, homeless, and so on yet people think they deserve extra because they did the work they agreed to do when accepting a job. Be thankful to be earning an income and even more thankful if you are lucky enough to receive any type of added bonuses.
You have some good points, but... Let's say I went to a restaurant and the bill was $500, but I tipped $5? Is that ok? There are no rules at the restaurant that say how much I should be tipping. It would just be a crummy thing to do.
There are no rules that say Apple should give employees XYZ, but giving a preachy credo card and a a t-shirt are pretty corny.