If I'd been getting an extra week beyond that, a long-standing perk that's used to help recruit employees, I'd certainly be annoyed and considering my options if it gets taken away.
People consider their options every single time they drive to work. No one is arguing that when perks are taken away you can be sad. But it's not like employers aren't disappointed by employees often too and still keep them for weeks, months, years longer after the disappointment.