Several countries (e.g. France) use the word pound (livre) to mean 500g, which could confuse visitors into thinking something non-metric is being used. I noticed that in south America.
Also in Italy, when dealing with agricolture, forestry, and related services, non-SI surface units are still commonly used, at leat in the north:
https://it.wikipedia.org/wiki/Pertica_(unit%C3%A0_di_misura)...
[0] These days, and selling butter in 200g packages to keep the prices seemingly low.
And that's why i do my shopping now based on €/kg. There are some very telling differences between even the same manufacturer: last thing i was looking at was gin [the drink] € per litre. Just a visually minor difference in bottle size was a substantial difference in a) cost and perceived value and b) cost and actual value.
Note that nobody I know below the age of 70 uses the "livre" unit in France. It's something you see pretty much only in old recipes