Could that be a UK thing? I wouldn't know tbh, because between mixing yards and miles versus sticking to imperial units in the 21st century, the latter is definitely crazier ;)
In Canada we have imperial for short measurements (inches and feet for lumber, people's heights) but metric for longer distances (kilometers for driving distances for example)
Yep, we mix them up. Distance and speed in miles, fuel priced in pounds per litre.
And fuel economy in miles per gallon!
Driving distances in miles, walking distances in kilometers!
And, though admittedly not really exposed much to the public, canals and railways both manage to mix chains in there, too... agh!
And thinking about the height of mountains in meters even though the reason for walking up them is because they reach a certain height in feet.
I don't see the issue. Miles and yards are both imperial units.