It's more to do with natural language and ambiguity rather than snobbery. When saying the name of a site (that happens to also be its domain), one won't say "hyphen" or "dash" but just the name itself. The person hearing this won't hit the correct site when they omit the hyphen. Then you'll get into situations like this...

"Visit this site, the address is 'blah blah dot com'"
"Ok, got it, thanks."
"Oh wait, that's 'blah hyphen blah dot com'"
"Ok, got it now"

When they next get to a browser, they immediately type the address without the hyphen and end up on some type of fetish site.