Potentially they could have semantics in the future, but right now they don't. If you make a user agent that relies on them having those semantics, that user agent will misinterpret a lot of web pages.
I can create CSS to style the two tags accordingly, and in within my own work I can make them mean different things to the tools I use to create and manage html.
There are only two hard problems in programming: cache invalidation and naming. When programmers give something a name inconsistent with it's behavior, it's going to cause a problem.
