There's really nothing hard about using vectors; they'll just be blurry because they're probably not pixel-fitted. Also, complex icons are much smaller and faster to render in raster format.
I seem to recall a graphics designer blog that compared a vector to an image that was tweaked at the same scale resolutions. The differences were staggering. I don't think vector graphics are a panacea anymore. I'll see if I can find the link, was rather eye opening.
While that link makes me appreciate that SVG speficially might be hard to work with and that simply scaling everything proportionally might not make for good icons across all sizes, I remain unconvinced that vector icons are hopeless. Perhaps SVG's have the ability to do what I describe above, or perhaps we need a more powerful vector graphics format to work with.
So maybe that will simply add to the "tough for non-Retina users" momentum...