That depends on the licence, though. GPL3 requires that obtaining a license should not be harder than obtaining the binary distribution. If you use some kind of obscure version control system for your source code but link the binaries in your website, you're entitled to the source code in a similarly easy way.

The developer could exercise their rights and insist on sending you a DVD with the source code on it (and make you pay for materials+shipping) but throwing up difficult burdens is clearly forbidden by the GPL.

Some more extreme licenses grant you, as a user and as a developer, a lot of rights, but also a lot of burdens. I don't think the stricter ideological licenses such as GPL are used much by people who distribute their own code and then decide to make life difficult for their users, though. It's likely that the only cases where this rings true are people relying on GPL code that then want to avoid fulfilling their obligations to their customers.