Because of the cost of medicare. Which is basically a combination of demographics and the cost of medical care, with the cost of medical care being the driving factor. Doesn't that sound like an arena ripe for disruption by startups?
The energy crisis that will inevitably come, doesn't that sound like an arena well suited for startups?
There seems to be a tetonic shift right now that a lot of people have a big stake in ignoring.
VCs are meant to provide capital to entrepreneurs who need capital. Web apps don't really need capital in the initial stage, everyone knows how easy it is to boostrap your web app these days. That's why angels are growing in prominence - becuase they fit the funding level a lot better.
The VC's should be giving their attention to companies that require greater investment - my two examples are healthcare and energy but they are just 2. Solutions to billion and trillion dollar problems yield large returns on a few hundred million dollars. Can you see that coming out of the web sphere?
But your average software VC can't really pivot over to those fields, they have expertise in this area, and don't have the skills to evaluate bio-medical and energy startups. So instead of realizing this and packing it up and going home (or at least hiring some new people to evaluate deals) they are just strip mining the web app space until there is nothing left.
The guys in those fields don't necessarily have the entrepreneur mentality of a lot of software guys, so they aren't seeking the VCs the same way hackers are.