I see the analogy but there’s a pretty big difference between hiding your face and hiding your device’s IP address. The former is a social norm going back tens of thousands of years, the latter is an arbitrary and artificial artefact of man made technology in the last 30.
A better analogy is sending mail with either proxy return addresses or none at all. Both are socially acceptable in most circumstances.
I also find blanket proxy bans reasonable: it’s akin to refusing service to those who wear a balaclava to a store.