I don't think it was unfair at all -- people just assumed that it would be shipped on CD, which is a mistake, plain and simple.
In the days of the crossover from floppies to CDs, many people got "bit" by software that was shipped only on CDs because they didn't bother to research what kind of media te software came on.
Apple makes it VERY clear that Tiger comes on DVD if you take the time to research what kind of media is included in the box. It is explained on Apple's Tiger page, as well as the Tiger order page, as well as the box itself that the media contained in the box is DVD, and DVD only.
For those that just click through the order process going, "yeah, yeah, yeah, just charge me and ship it to me," well, not to be rude, but you kinda got what you deserved.
Floppies were the "standard" method of software distribution 20 years ago, then it switched to CDs... and now, DVDs. It has never been "O.K." to purchase a software package blindly without first checking 1) system requirements, and 2) kind of media.
If you purchase a set of 15" tires, but your car has 14" wheels, whose fault is it? If you purchase a gas clothes dryer but your home doesn't have gas dryer connections, whose fault is it? If you purchase a new window pane but forget to measure the window first, whose fault is it?
For those that got "bitten" by the DVD-only thing, it sounds like the urge to spend money muscled out the urge to check the requirements and media first. No, Apple didn't display a huge, flashing, "Tiger ships on DVD only!" banner on their order page, but they did provide the information where it was needed: on the Tiger page, it's right under "What's included with Tiger," and on the purchase page, it's clearly written under "What's in the Box."
There's no blame to put on Apple -- those that didn't bother to look up the information they know they need should be slapping their own heads instead of looking to blame Apple.