Just like with PDF, you can embed fonts in HTML so everyone has the same font.
But yeah, agree with your overall point, PDF is currently the easiest, most well-supported way of sending stuff that doesn't fudge around with the design. What you send someone is almost guaranteed to be what they see, unless they use some weird PDF reader.
An epic thing you can do with PDF though is show an image of the font you want to show, and have a super common font like Helvetica hanging out behind it, so the end-user doesn't even need to render the font, it's just an image.
