Me too! I was all about FontAwesome for a while, then I discovered http://iconmonstr.com (which has far more icons), and now I just use the SVGs from there for everything.

Yes, using fonts for icons was always a wee bit of a hack. The only real major advantage over SVGs was easy sizing for being inline with text.

The implementation with the :before class definitely qualifies as a bit of a hack. No question.

Some of the icons themselves represent something of a universal language for websites. Using those symbols in a typeface is similar in some ways to character based languages like Japanese or Chinese. So I might argue that icons as fonts are quite an appropriate use.

The compelling feature of icon fonts over svg used to be IE8 support.

But then there was IE9 mobile, which didn't support @font-face. I remember coding detection for that, and creating a script that automatically generates png versions and the required CSS of the glyphs in use. Sigh.