It's fizzy...it's ginger...it's phenomenal!
The ginger in the ads is a pun on the West of Scotland "ginger" meaning "fizzy drink". The first flavoured fizzydrink was ginger beer, and that became a metonym there for all carbonated drinks. "I want a bottle of ginger" "What kind of ginger?" "Lemonade" The word "ginger" also has the hair colour thing, as well as suggesting activity and livliness. The challenge in Gaelic is to make a pun, with either the word for a soft drink, the colour, or iron involved...