I absolutely hate the idea of serving garbage byte to users - even if it is only 500 kB worth.
The internet already has enough useless cruft. CNN loads 4.9 mB of data with no adblockers. Fox News loads 2.6 mB. MSNBC loads 4.2 mB. The Guardian (US Edition) loads 4.3 mB. Padding a site with 500 kB (or really any amount of bytes) is unfair to mobile users without unlimited data plans.
A user who visits your site twice per week and navigates to 5 different pages on your site each visit receives about 12 mB of garbage bytes per month.This isn't that big a deal if only one site is doing it, but imagine if that's how all sites did it?
If people would support the site all the garbage would disappear for everyone. If a dollar for a byte is a bit too high, you could place a ceiling at $5000 - it would be around 100 bytes for a dollar.
It would be an alternative to ads. Ads are a padding plus unfairness and dishonesty. They also track you and run code on your machine. This would be just a padding.
A creator has to eat and people don't have to use his site. Those that like it and would want to make it even better can pay.
And don't forget that a first step was to create a _lean_ website. 200kB + 500kB padding would still be more than 2 times less then any website you mentioned. For this to work the website would have to prove from time to time how it would work without useless bytes. You could also serve less useless bytes.
However it could still work with added latency instead of bytes. Example: 50ms every 100kB.
The internet already has enough useless cruft. CNN loads 4.9 mB of data with no adblockers. Fox News loads 2.6 mB. MSNBC loads 4.2 mB. The Guardian (US Edition) loads 4.3 mB. Padding a site with 500 kB (or really any amount of bytes) is unfair to mobile users without unlimited data plans.
A user who visits your site twice per week and navigates to 5 different pages on your site each visit receives about 12 mB of garbage bytes per month.This isn't that big a deal if only one site is doing it, but imagine if that's how all sites did it?