A clever MSFT plan. It motivates the Firefox team to increase the number of releases, so they eventually stop the actual development and realize that the infinite supply of free cakes is easily convertable to cash.
Do you think there's a big market for second hand IE branded cakes? ;-)
EDIT: And if their goal is to deliver the best browser, it would be more efficient to buy GOOG shares with the money extracted from cakes. ;->