Ref: It’s appropriate everywhere because as a language of Scotland and supported by a majority of people in Scotland most people want it used more. http://www.gov.scot/Publications/2011/08/04140925/0 The idea that because there are no native speakers of Lothian Gaelic left there should be no Gaelic signs in Lothian is utterly ridiculous. There are Gaelic speakers in Lothian and in order to promote and support the language we have Gaelic signs. It’s an important part of Scotland’s cultural identity.
I think the real question is why are there so many vocal people against Gaelic, arguing it should be marginalised or only used in certain areas because it hasn’t been spoken locally as a local dialect in living memory.
We didn’t have an internet readily available until the 1990s yet you seem to have embraced it readily as a communications tool. Society changes and we should not be confined to what was “traditional” in the recent past, because doing so would be to be arguing to do without the internet, mobile phones, the Scottish devolved Parliament, and in the near future driverless cars. Why can’t you accept that society is not a fossil?