Buying expensive bikes and parts...
The beauty of being free is that a person can make a choice that's best for that person. A very great thing, that.
Myself, I don't "push" with cycling, so I don't particularly need top-of-the-line stuff that'll handle a downhill blast via MTB or a near race-pace clip on a road bike. I just plod along at the speed I go, on mostly pavement and light mixed-surface routes.
For me, a ~$300 pre-owned bike that's tougher than most, easily modified, and supportive of add-ons (like fenders, say) -- that's the sort of thing that works best for me. And I'm completely okay with the next dozen people who pass me on some expensive newer model that suits them.
Haven't had many bikes, over the years. My latest: a mid-90s Trek 970, configured with 2x11spd drive train and a custom wheelset. Works very well. Pricey add-on parts, all things considered, and didn't have a stash of older parts of this sort, so the overall build price went well over $1K, which was a far cry from the bargain-basement price for the original frame+fork. But then, everything was gone through and updated. Not cost-effective, but more bomb-proof than most and it's geared how I need it. Works for me.
Plus, with "expensive" options out there, it's always fun to see what people end up selecting.
My own imaginary "plus 1" bike, if I get to the point I want a hot little number hanging around: a custom UTB or Adventure model bike from Rodriguez (R+E Cycles) in Seattle. Custom-geometry, relaxed/slack fit, step-through format, low-geared, etc. Would likely be well north of $4K, by the time it's in my grubby little hands, if I were to pull the trigger on such a bike. Thinking about it.