You mean you change your IP to a US IP to watch shows/movies in a non-US country? I think Hulu & Netflix can detect VPNs and restrict access. I just use a SOCKS5 proxy with a high reputation score.
VPNs were originally intended for networking multiple devices under one subnet. So... that.
To expand on that, as a security measure it allows a company to provide an encrypted tunnel and their own DNS to their internal network even if you're in a coffee shop.
Can anyone explain to me how they can detect a VPN?
do you mean detect your location or detect the fact that you're using a vpn?
because there are plenty of API that'll tell if you're using one
+if you have a huge database you can detect duplicate IPs