If work doesn't produce anything of value (which isn't the case here, just hypothetically), then the "created" jobs are bad for the economy because they divert resources from productive areas. It's another form of the broken window fallacy.

Job creation is just about the worst 'benefit' that can be ascribed to a project. Practically any expenditure can be tied to it. Using this argument just puts your project on par with digging ditches and filling them back again. This is not something a LHC promoter should be proud of, in and of itself.