I have often thought about why someone would take multiple medications. I didn't think it was harmful or necessarily helpful, but I felt like maybe I was in the minority only being on one SSRI myself. My one psych medication seems to help me function, and since I am not really clear on my exact diagnosis other than "depression" it seems like a good one pill fits all that works for me.
If people feel better when they take medication, whether it be one med or more, I think that is a helpful thing. I have tried the holistic route myself in the past, but it didn't really work for me. I trust the doctors to know what they are doing.