[burntoutfire]

I think the main reason is low initial cost of investment. It's just easy and cheap (in terms of money/effort) to create a website, so people make lots of them for whatever far-fetched ideas they have. They don't intent to build a website for decades to come, because they don't know if they'll even continue to maintain it in six months' time - so they naturally gravitate towards the cheapest/easiest/most ephemeral solutions that get the job done for now. At scale, it results in the web resembling a shantytown.