I’ll comment on cycling seeing as I’m a little familiar with it and you might be able to extrapolate the mindset out to other subjects.
First, the quote above is a false dichotomy, the cyclist can have super light parts AND take a dump.
I think all cyclists who have ridden up a hill in a heavy bike and a light bike know that weight matters. The serious amateur cyclist is often middle aged with significant disposable income to spend on their hobby. Once they have all of the actual bicycles they “need” (a road bike, a track bike, a hard tail mountain bike, an all mountain mountain bike, downhill mountain bike, fat bike, bad weather road bike, cyclocross bike, hybrid bike with child seat on the back, then another road bike that is significantly better than the first one they bought) they start looking for ways to upgrade their bikes. The only real way to upgrade a road bike is to make it lighter and/or more “aero”. Once they’ve done the big things like wheels, they are forced to look into areas where the gains are progressively smaller.
Because they know they are spending lots of money on something they do some research and end up finding the cycling websites and a group of people who will encourage their spending habits.
When they actually make their purchase it may not be the most expensive and lightest piece of gear because that may be out of their budget, but it will be expensive and light. They will then be forced to find noticeable gains from this new piece of gear.
“Yeah man, I’m putting out the same watts as before but going .00127% faster, remember that race with Bob where it was a photo finish? Well with this derailleur I would’ve won it by 2 cm!”
This is partly to justify it to themselves, and partly to justify it to their partner, or wife, let’s be honest, it’s mainly men who spend like this.
They will be back on the cycling forums now because they became attached to them, and they will be both promoting and defending their purchase to keep up the illusion that it was worthwhile. Promoting to the newbies who are looking for advice, and defending against those who could afford even lighter gear. The fact that the most aerodynamic gear is not necessarily the lightest gear (wheels are a good example) leads to a fertile breeding ground for discussion.
“Yeah, I tried the XL5 with the drilled cogs but I found the holes created turbulence close to the rear wheel which actually increased the drag enough to offset the weight advantage.”
“You must have the Mavic DR1 wheels do you?” (It’s in their profile)
“Yeah great wheel.”
“It is, but it doesn’t play well with the drilled XL5, you need to upgrade the spokes in the wheel to the 2016 Aero Delta, then you will get the advertised gains from the derailleur”
“But the Aero Deltas are .0052 grams heavier for the set”
“That’s the 2015 ones, the 2016 spokes are .0005 grams lighter than the 2015 ones but have a new profile designed specifically to interact with the drilled XL5 in a way that actually produces thrust from the turbulence eddies.”
Etc.