To pay USD $20 and unload a problem to some 3rd party service takes under 30min, while running a scalable, high performance web-server on low budget is hard and time consuming - even impossible for devs with no sufficient devops/admin skills, which is sadly a majority.

Back in the day, as a student with no money and a time to spare I used to do it all myself too, guerrilla style. Nowadays tinkering with my private servers would mean taking time from my real job, and that just doesn't make sense financially, my time is way more valuable and scarce now.

That's why we have the economy of specialists in the first place. One can do everything in DIY fashion, but in our civilization it's usually cheaper to hire a plumber's or carpenter's services than to invest in learning the skills, buying the tools and then doing it, if it's not your primary source of income. It's no different with CDN services.

For the rest of us who would rather not let our site fail, a quick one time $20 tarp over dumpster to handle the traffic in the meantime is good.

If you are only talking about food, it may stretch a bit further, but you’re still far away from the majority of countries.