I want to clarify that when I say "0% web development going on", I don't mean that scientific programmers don't do web development (they do! a lot!), I meant that people don't pick it those languages in general if they are only doing web development without a numerical/scientific/statistical aspect to it.
What would be interesting is, do you know of any teams or companies using Julia in anger in a non-scientific setting, with programmers from a non-scientific background?
The scientific Python community certainly makes good use of all the Python web tools!, and being a "scientific stack" in no way precludes the need for general purpose frameworks that can also be used by others. It's at least as much about people and community and habits as about the tooling...