Basschat Yellow Card mate , one more and it's a Red 🤣
All joking aside, multiple pickups means that when you're at a (new) gig and one or other of them is either sounding shite or feeding back, you have the other, and a decent preamp allows you to balance the contribution of each to the overall sound both in terms of relative volume and tone. At the gig itself, 'high-end preamp' is an important idea in terms of functionality, perhaps less so in terms of tone. I used to use three channels in order of preference 1) Mic 2) Piezo 3) Mag. For sure you can get away with 3) alone unless you're on guts, but 1) alone is always more satisfying and 2) always a little less so