I don't feel the need to defend arrangers. They have kept me from having to get a real job for 30 years.
I used organs and peripherals for arrangers before they were invented.
Last night I had two world-class musicians join me. One is a super-talented guitar player, the other a harmonica player, just moved back here from Nashville. Both have been pros for many years. Both were overjoyed for me to pay them $100. each for four hours work.
We sounded great and it was a privilege to work with them. However, the bottom line is I didn't really need them. It didn't put another dollar in the cash register or the jar.
I'd forgotten how much more work it is to set up for a "band". Bigger mixer, extra cables, extra mics, stands, etc. Had to reposition speakers, announce songs and keys. . .sorta like a bachelor getting married, you have make a few changes!
Both brought their own small amps. I tried to patch them through the main board so I could record, but if I got the signal loud enough in the mix there, they were too loud for the audience, which of course is the primary consideration. So I didn't get good recordings. Too bad, I would love to have recordings of it.
Getting off topic, I guess, so I'll shut up and eat breakfast.