It's not about altruism - they're talking about benefits for themselves just as much as for everyone else: we can all do better. Some things can't be done alone nearly as well as they can by a collective, which is why we have government in the first place. Sure one could say that simpler collectives like religious organizations, corporation and charities can accomplish collective goals, but even they operate at levels too small and single-minded to accomplish goals as large as an interstate highway system or an international space station as well as government does. These people want better roads and I think are seeing many areas in which our whole country is lacking and wondering why we are so hesitant to do something about it, considering how easily it appears we could afford it. I think often times people are stuck in their ways not because they really don't want anything else, but because they don't realize the consequences of their choices and what really matters. Have you heard the stories of the areas that have discovered that housing the homeless ends up costing less than leaving them homeless? It takes someone with a vision to suggest such a counter-intuitive improvement. People who measure *everything* in dollars are missing a lot. And now some people are speaking up, pointing out, hey, we can all live in a better world for all of us. Don't you want to try? It may mean fewer dollars in individual pockets, but I think they're proposing that the benefits outweigh the cost for *everyone* affected, and can we agree to find a better balance here? Just think about it... too many people just don't think about what really matters and don't realize what all the impacts of their capitalist upbringing are. As the late great Paul Wellstone said, "We all do better when we all do better."
Of course the non-wealthy would be proponents of raising taxes on the wealthy, but when wealthy people themselves are saying the same thing, it's really time to call into question whether the weight consensus should really be shifted in favor of higher taxes on the wealthy even if there are hold-outs... seems like it's time to at least talk about it.
"Truth never comes into the world but like a bastard, to the ignominy of him that brought her birth." -- Milton