emerge use "proxy_http" setting in the make.conf file to setup a proxy server. I think it also should work in the same way for emerge-webrsync. Currently you have to specify http_proxy in an envirement. It also should be man file or --help for emerge-webrsync. Reproducible: Always Steps to Reproduce: 1. 2. 3.
"http_proxy" is not used by emerge or portage at all. It's only used by wget. Personally, I think it should not be listed in the man page because of this. As the default FETCH_COMMAND is wget, I have no problem with it being listed in make.conf.example though. What you are asking for here however is that emerge-webrsync source make.conf before doing it's thing. The equivalent of that will happen when webrsync is integrated into emerge.
Jason, thank you for understanding the issue. Indeed it would be logical to have all proxy/mirroring settings in one place. I'll leave this issue for "later" resolution.
*** Bug 365029 has been marked as a duplicate of this bug. ***
*** This bug has been marked as a duplicate of bug 185048 ***