I've upgraded memory on every laptop I owned. In Serbia (and I assume other smaller markets) you can't just freely configure your laptop, you pick from a selection that was imported, and you typically have to make some kind of compromise between performance, display, keyboard, etc. Having option to upgrade RAM or disk increases your choices in other variables.

Last year I bought MacBook Air, and only options available immediatelly were 8/256, 8/512 and 16/256. Since I wanted more RAM and more SSD I had to wait 2 months for delivery.

For some reason upgrading memory seems more cost efficient than just buying a better computer. For example I bought a mini PC for 140 EUR and upgraded to 32GB for additional 80 EUR. Meanwhile actual 32GB mini PCs with rougly equivalent CPU start at much higher prices.

I've done it more than that because I've been buying refurbished or used laptops (generally ThinkPads) and maxing them out cheaply. If I were buying a new flagship machine every 5 years or so I doubt it would matter to me. But that used market is extremely important for keeping this stuff out of landfill for a few more years.

Counterpoint: I've maxxed out memory in all my laptop and desktop pcs so far, even the machines for secondary uses I max them out using budget parts.