My thoughts on Shelters:
First of all, I apologize if I unintentionally semi-plagiarize an idea someone else had in previous threads when people were expressing ideas about Shelters. I do recall that most everyone felt it would provide some sort of victory point, even if it was negative. I have been thinking about the name "Shelters". That suggests something different to me.
No one has problems with living in an Estate. And if it is your Duchy, Province, or Colony, obviously you are going to have a place to live, and a nice one at that. But a Shelter implies a pretty low budget residence, maybe even somewhere below a tent in some cases, though a tent could certainly be considered a shelter. On the other hand, if you have a choice between a Ruins and a Shelter, I think the choice would be pretty obvious. So I feel with the name "Shelter" and the fact that they will only be in your starting hand, not in the supply (since there are only 18 of them), it will not have any victory point value. Rather, I believe its main function will be to exist in games that have Ruins, and thus it will serve as some sort of Shelter from the Ruins. Unfortunately, they still take up space in your hand, like a starting Estate. And we know how quickly we try to get rid of those Estates. So now the choice will be whether to get rid of the Shelter and face living in a Ruin, or stick with the Shelter, which will slow down your upgrade to a better place of dwelling.
Consider the names of the other Alt-Victory Cards we have. They pretty much all imply something positive. Who doesn't want to be a Duke or a Noble? Every good Castle needs a Great Hall and a nice Garden, and of course, a Harem. And isn't it a good thing to have a Vineyard to make some good wine along with some Farmland to grow some good food to go with the wine? Also, who wouldn't want to have their own Island? Having a Fairgrounds suggests a happy occasion, and sending someone down the Silk Road with goods to trade means you are going to get some pretty nice stuff in return. Of course, there is Tunnel - not the greatest place to live, but this Tunnel is a mining tunnel that gives a rich reward. Shelters just doesn't evoke any positive images to me like these others do.
I may be totally off on this idea, but the name of the card just seemed to fit that concept. If they are as I suggest, then I could see Donald explaining their purpose in a similar way.