[rchaud]

IP is not used for user geolocation (or at least it shouldn't be) because it can be spoofed, e.g. via VPN connections.

[minimaxir]

For analytics purposes, indeed IP isn't used for that reason (although nowadays IP is sparsely used at all in analytics due to legal PII risks), but for responses to a "what's nearby?", it'll generally be relevant despite the possibility of VPNs.

[fourseventy]

IP addresses are used for that all the time...