Across the pond from MAN is different. Again, you get the feeling that if MAN can support long haul to the east, then it should be able to do to the west to places like Boston, Vancouver, Washington, Montreal, Dallas etc.
You are quite right. It is different. The east bound routes are all to massive airline hubs, where traffic gets redistributed to points North, South, East (and a little west). It is much easier to make this kind of network sustainable and that is what we see to the West as well, with the American carriers. I don't believe there would be enough demand for those cities alone to justify daily service on a 'legacy' carrier. The only places with significant service that are not hubs are places with massive leisure demand, like Las Vegas and Orlando.