Most of people complaining were going to sell the iPod to get money instead. That's not what Apple wanted, otherwise they would have given a bigger student discount, not free iPods.
Their original goal was to put iPods in the hands of students who were not originally going to buy one. Then they could make an iTunes account to spend on music and apps, which are more profitable to Apple than the iPod themselves anyway.
If everybody just buy the Mac and resell the iPod on craigslist, they sell it to people that likely were going to buy one anyway (so they lose the profit of the hardware sale), plus if these people are cheap enough to get through the trouble of buying someone else's brand new iPod through craigslist to save money, they probably pirate music, too.
Now, instead, this forces you to actually use iTunes or the App Store. I bet most of people that will be getting those gift cards don't have an iTunes account already, so they'll make one, spend the 100$ and learn how the Mac App Store and such work.
After the 100$, they will be more likely to come back to iTunes / Mac App Store since they now already have an account and know how it works.
Apple then fulfills their original goal again: Making you spend on content.
couldn't say it better my self! +1
