All stations are in effect JIT
The issue is that every year more stations close. Its becoming more centralised with supermarkets etc in effect gaining a larger share each year.
Whilst there are more stations in higher population dense areas, per head they are much lower.
What compounds the issue is that there is far less buffer in the system (this is basically what JIT does). No need for thousands of extra stations all sitting on thousands of litres of fuels, when far fewer stations, being topped up frequently normally seemlessly support the needs.
When there is supply disruption which happens in bad winters etc as well, then as long as they can keep it just high enough to not cause any massive panic then no one notices, a few stations may run low but no one notices. If there is just enough buffer there despite JIT then all good.
As soon as the supply falls below the demand it quickly becomes apparent.
Every industry, which most do, that operates JIT has the same issues. Some will get round it with emergency protocols, such as some emergency stock etc, but in general its the biggest failing by some margin of the whole system.