This year, I asked my family to donate to a charity as their Christmas present to me- and they did! (my mom donated to the humanitarian aid fund). We talked about the experience and what it was like for those involved. My mom and sister-in-law said the "Share the Gifts" request caused them to think a lot more about the needs of those in the world. Each also shopped for the right charity in the same way they normally shop for anything- e.g. my mom was in and out, and my sister-in-law researched 30 or 40 different options trying to find the best bang for buck. I talked about reasons I thought the project was valuable:
1) 30$ for you and me means a lot less than 30$ means to a poor family in the Philippines. Just as you would derive more utility from earning $30,000 than Bill Gates would, the same amount of money brings differing levels of utility roughly determined by the economic class of the consumer. Therefore, if the "love your neighbor as yourself" principle means you esteem your spiritual brother or sister's utility as much as your own, you will give 30$ to another up to the point where their utility meets yours. Therefore, "Share the Gifts" is a step in this right direction.
2) The giver of the gift is likely to receive the benefits of charitable giving [increased health, wealth (a little over 3:1 ROI), and happiness- see Arthur Brook's "Who Really Cares"]. The person who asked for obligatory Christmas presents to be diverted might also receive these benefits. Plus, the incentivized giving provides practice likely to increase the giver's skill at discerning which charities offer the highest benefit/cost ratio.
3) I often find possessions to be burdensome (have to manage them and cart them around when I move, and I usually purchase the high utility items I want anyway), so having fewer gifts is a bit of a benefit. I realize this prong probably doesn't apply to many.
4) There are definite economic benefits to high consumer levels. Though I think there is excess consumerism in America, I wouldn't advocate a drastic reduction in consumption because of the clear connection between GDP and consumption levels. However, diverting spending from frivolous luxury products to Heiffer International (buy a goat or chickens for a family who would raise it) or other high social benefit/cost products or services maintains the benefits of high consumption levels while simultaneously building the "helping people" market.