Uuummmm.....just to name one reason: a lot of amps are only available as mono-blocs: most VTL's, CJ Premier 8's & 12's, many large Krells, the biggest Bryston's, etc. etc.
To get the watts & current of many of those in one stereo amp, you'd need a forklift to get it into your house. At any rate, to get the precise sound quality & power of VTL 450's say, or CJ Premier 8's, or some Cary monos, you need to buy those, because they don't make 1-unit versions.
But if you don't want mono-blocs, don't need them, not interested, then don't buy them. Personally, I've always lusted after big VTL mono-blocs, or Cary 805's......
To get the watts & current of many of those in one stereo amp, you'd need a forklift to get it into your house. At any rate, to get the precise sound quality & power of VTL 450's say, or CJ Premier 8's, or some Cary monos, you need to buy those, because they don't make 1-unit versions.
But if you don't want mono-blocs, don't need them, not interested, then don't buy them. Personally, I've always lusted after big VTL mono-blocs, or Cary 805's......