The global average it's 0.2% or 1:500, however Taiwan averages 2.3% though Android tablets hit 9.6%. And, some websites see significantly higher rates.
id imagine the company has web apps (internal and external). why support multiple stacks for what is not even remotely close to their core competency? isomorphism, for example, is a big advantage for both maintainability, community support, and rapid delivery
Who owns Javascript? ECMA is a public standard.