To have "a good ROI via recruiting," never mind the etc., he just has to improve his profits by more than 40k per year, by making better products than he would have otherwise, by hiring better people than he would have otherwise --- or by having to pay 40k less per year in salary, although that seems less likely. Although the chain of causality here has a lot of randomness attached to it, if he has a few million dollars in revenue per year, such an improvement hardly seems implausible.

The flip side is that spending a lot of money on something apparently unnecessary might incline you to spend more money on things that are actually unnecessary.

(I'm assuming "a good ROI" means 4% per year.)