I'm all for real performances from real people - I personally find no greater pleasure than getting into a great feeling groove with good players - but canned music, loops and other "non-performance" production is to a degree a reality of todays musical industry. I don't always use Band-In-A-Box (or Jammer, or sampled loops, etc) but I do use them often - in particular when I'm arrangeing and producing basic demo's for songwriters who can't afford to pay me to spend 10 hours trying to get a solid drum, bass, piano, etc, etc, track. With BIAB I spend 10 minutes entering a chord pattern and the "band" is ready to put down a solid (although somewhat uninspired) backing track.
A songwriter I work with (with my musical assistance) got a song placed in a movie direct from Band-In-A-Box (useing the actual demo we sent out). I added real guitar and some string lines (and added a bridge to the song) and we had a great singer (a great singer is always a must have!!!) - but the point is the song was placed with the original BIAB performance (and although I almost always tweak BIAB - this particular writer did not want it tweaked).
Now I'll be the first to admit, that when we sent out the demo, there were certain BIAB "riffs" that I thought were too obvious, but it sold (so obviously my instinct as a producer was dead wrong).
Now I agree with Peter D that canned music does hurt some working studio cats (hell, when drum machines first came out I lost almost all the studio work I was doing - until I bought a drum machine and learned how to program it better than the keyboard players!!!) However, home studios have hurt alot of "real studios" which in turn hurt alot of studio cats (so who will cast the first stone???). That's the way it is and we have to accept that (and as a working musician for over 35 years I feel I'm qualified to make that statement.
I am not in favor of useing completely canned arrangments - but as stated in my previous post, I'm not convinced that useing a computer generated bass line (or drum beat) is much different (from a creative standpoint) than having a person create a bass line - as a writer, arranger or musician - you still have to react to that part and create other parts which work with it.