They were an actual monopoly for a period of time in the 70s and 80s, until Cooley started up; and then they started selling non-core brands from the mid 2000s. Bushmills first, then Tullamore Dew, then Paddy.
Probably some attempt to create a brand they can sell off; or conversely keep if they ever sell the actual distillery.
Until quite recently, it was rather hard to find much reference to Jameson, Powers, Paddy (they've sold the brand but still make it), Midleton and Redbreast being from the same...
Its Bushmills, same owners.
Bushmills 10 (single malt, the white/red/black 'colour' brandings are blends) can be got for buttons coming up to Christmas and is an exceptional example. No smoke, obviously.
On the Scotch side of the cupboard, Talisker is my most regular I'd say.