As a web-developer/webmaster/sysadmin (a fairly common role), I'm confused as to the separation between the different communities.
I get that building HTML for a webpage is more of a coding question, while SEO is more of a webmaster question. However, many of these boundaries are very blurry, and I see questions closed as 'not being a webmaster question'.
If I build a reputation on Webmasters that allows me to ask a question and put a bounty because I want an answer, it might get closed for being off-topic, even though it's closely related to being a webmaster. (Say a question on how to code a sitemap - something webmasters need to do, though technically a coding question.)
This discourages me from spending a lot of time building a reputation on one of the smaller Stack Exchange sites. I'm sure you've discussed this before, but I couldn't see an answer as to why there are these boundaries, and why my reputation doesn't flow between them.