[justabystander]

The VPN changes your network route. This can get you around geographic locks (services that only work in certain areas). It can also get you around traffic issues, if your ISP has technical/political routing issues. Like with Comcast/Verizon refusing to add additional peering because they wanted to double-bill netflix traffic.

Some VPN services also advertise additional privacy or anonymity, but trusting a stranger to not sell you out to their local government isn't usually a good idea.

From a business standpoint, you may want web and network services without exposing them to the wider internet. So they're only accessible on IPs in local subnets. VPNs will get you inside the wall.