For the same reason that some Welsh people speak Welsh. Gaelic is the traditional language of Scotland so many people continue to speak it as they feel it is an intrinsic part of their cultural heritage.
A person who speaks Scottish Gaelic can be called a Gaelic speaker or a Gàidhlig speaker.
It is mac in Scottish Gaelic.
The English language? Béarla (Irish) Beurla (Scottish Gaelic). As an adjective? Sasanach (Irish), Sasannach (Scottish). "The English (people)" na Sasanaigh in Irish; Sasannaich (?) in Scottish Gaelic.
"Gaelic" can mean "Irish Gaelic' or "Scottish Gaelic". They are classified as two distinct languages.
The Scottish Gaelic for 'brother' is bràthair.
It is òran in Scottish Gaelic.
in Scottish Gaelic: facal.
The Scottish Gaelic is do charaid.
In Irish d'fhíorghrá;in Scottish Gaelic: ?
It's Scottish, but not Scottish Gaelic. Originally a Scots variant of Margaret.(Margaret is Mairead in Scottish Gaelic.)
ùr is the Scottish Gaelic for 'new'.
"Acceptance in Scottish Gaelic."