I don't know how the maths works in the USA. But I used to commute into London, at a cost of 15 pound a day. Times 230 days a year, that's 3,450 pound a year. I pay 40% income tax and 2% national insurance on that money, so you have to pay me (3,450 / 0.58) or 5,950 pound a year extra so that I have the same money in my pocket after paying for my train ticket. In addition, my employer pays 15% employer national insurance, so it costs them 6,840 pound a year to put the same money into my pocket.
That only pays for my train ticket. It doesn't pay for me driving to the train station, it doesn't pay me for three hours commute a day, it doesn't pay me for exorbitant prices in London to get some food at lunch time.
Now if I work from home, I do more work per hour because I'm not exhausted from the commute, I sometimes work longer because I'm in the flow and don't notice that it is 5 o'clock or because I just want to finish something and don't have to leave to get the train. The employer saves the office space.
So this is a win-win situation for everyone. If you don't count the benefits for the employees, just realise that given the choice between job A where I work from home, and job B where I go to the office every day, even spending 7,000 pound extra money from your annual budget doesn't manage to make your company more attractive.