Where does the tax paid by the company come in to play? And the tax paid by their employees? The real math is total company paid tax + total employee tax - societal costs of presence. That's rarely less than 0 and surely not less than the negative societal costs of unemployment if they, as you mention, are better off unemployed.

The folly so many keep making is they think every tax dollar is necessary to support every company present. That type of thinking makes even one cent of avoidance appear to be a net negative, when amount paid overall can still be a net positive compared to impact of presence.