Given that English is not a major local language outside of Hong Kong, I'd expect there's a very high chance that an English-only speaker might need to interact with a Chinese-only speaker. It could be something like trying to relay their goal to a taxi driver or delivery person, or something as critical as trying to gain the attention of emergency services (I'd assume if you called the equivalent of 999/911 and shouted a location in the phone, even if you couldn't explain further, that would be enough to trigger a response)
Providing the English speaking audience the Pinyin gives them a chance to be understood in that situation. The translated only name is more likely to be unrecognized by the lisstener.
It doesn't seem so bizarre when you go into the Montreal metro and the signs say "Gare Bonaventure" instead of "Bonaventure Station", and that's in a country where English is nominally a supported language.