An Alpina is similiar to buying a hand made suit .
exclusive to yourself , reflects your personality and totally one of a kind.
Everyone has an M , not everyone has an Alpina.
And that is why the brand is successful , it is fluent in individuality and is more personal than BMW M. Alpina is also a very good talking point.
Everybody knows what an M is but not everybody knows what an Alpina is and that is why in Europe people choose these cars for the amount of exclusivity and of course every Alpina can be personalised to each individual aspect , again like a hand made suit.
I do not see Alpina going out of business , their exclusivity means that they will always have that special customer waiting for the right car and Alpina has a strong customer base in Europe and Asia.
There is an agreement that keeps the Alpina models away from the US Market because they would directly compete (in price) with respective M models. The B7 has no direct BMW M competitor.