Having spent considerable amounts of time in different countries and having visited four continents in the past few months, I've noticed that what many (including myself) consider to be a uniquely British or anglophone problem is in fact prevalent in a number of other countries - some of which have been metric for their entire existence.
I've posted images of signs in the UK using 'mtrs' for metres where 'm' should be used and I've discussed the nonsensicality of the use of kph instead of km/h in the British context, whilst lauding the metrication efforts of other anglophone countries in a similar metric limbo to the United Kingdom. Whilst I do stand by my argument that in the UK, we need to fully utilise our official system of measurements, and do so properly, I've come to realise that we're not the only country screwing this up.
The most common violation of the BIPM's accepted symbols for metric units is the (mis)use of 'mtr' to represent metre (and often its pluralisation to 'mtrs' for metres). The fact that this abbreviation is used in numerous countries does to some degree erode the validity of the argument for the universal symbol 'm', but not entirely.
Whilst it may be true that speakers of languages which use Latin characters may naturally guess that 'mtr' means metre, the whole purpose of having an internationally accepted symbol is so that everyone - regardless of whether their languages use Latin, Arabic, Oriental or Slavic characters will know 'm' is metre.
An additional point to note is that writing '100 m' is three characters less than writing '100 mtrs'. This yields some financial savings. The first is obvious. By using fewer letters, less time is used and fewer resources are employed. Even if the additional cost of the extra three letters is £0.00001, at an aggregate level, it could add up to a substantial amount of savings - this is common sense.
The second set of benefits from using international standard 'm' for metres (and only for metres) is the time savings and efficiency savings from misunderstanding. Mtr can mean any number of things (including being the name of the Hong Kong metro), whereas 'm' should only mean metres. I think it should be relatively simple to see why using the SI symbol makes sense - if only the real world worked like that.
The purpose of this post, is not to justify Britain's lax attitude to metrication, but to highlight an opportunity. When metric signs do become a norm (I have faith), we as a country can at least get it right and be an example to the world. We can ensure signs are posted in 'km' and not 'kms', 'km/h' and not 'kph', 'kg' and not 'KGs', etc. We just have to get to that stage first.