Why would anyone want class AB amp when class A always sounds better ?

Anytime I see the word 'always' in statements like this..... next! 

As no one in their right mind would prefer the sound of class-B xover distortion no matter how little.

There aren't any class B amps available in the consumer market, so this is no worries.

Wrong info to those reading this.
When listening at normal to loud levels "or" on hard to drive speakers,  Class-B xover distortion is just as prevalent in low bias Class-AB amps when pushed past the low Class-A bias point. And thats fact.
 
And I'll say it again.
For the same given amp that is comfortable within all it's design aspects either at 100w Class-A bias or at 5w Class-A, the 100w Class-A bias will ALWAYS!! sound better. unless you are listening to 110db horns
You can prove this for your self by listening to an amp with user switchable bias while listening. EG Parasound JC1 Gryphon Antillion etc etc.

Cheers George   

For the same given amp that is comfortable within all it’s design aspects either at 100w Class-A bias or at 5w Class-A, the 100w Class-A bias will ALWAYS!! sound better. Unless you are listening to 110db horns

Just to add to the end of that.
"Unless you are listening to >110db horns, then they will sound the same" because it only take 5w to get >110db horns going.

Cheers George