Well, first I don't use Ketarin several times a day (and sometimes only once a week, not more).
I don't perform update checks directly on fosshub host but author/software websites indeed, then use their download links for downloading files (only if a new version is available)
I'm not mirrorring fosshub so I don't consider fosshub (or any other host) bandwith stolen.
Sometimes, we cannot avoid using fosshub host when author/software official download links are only fosshub ones...
Secondly, I'm only a Ketarin user and it was initially a help request to the community, not a ketarin feature (or infrastructure) request to the Cannaverbe team, so I don't understand your last sentence, why putting them in the loop ?
Finally as a wonderfull tool, I already work-rounded your direct and "unbreakable" download security by using pre-download commands (opening a browser to the download page, then click save and continue the update/install process) and this solution respect your terms.