Me and my sister got into a debate last night about wedding registries. I personally think gifts should never be expected and it's rude to include any registry information in wedding invites. My sister believes since most guests have no idea what to give as a gift, including registry information isn't tacky and you're helping guests out by giving them an idea of what you like/need. So, my question is, etiquette wise, who is right? Furthermore, if you do decide to create a wedding registry, how do you go about letting guests know without coming off as being rude/tacky?
p.s. Sorry if this has been asked a million times already. I haven't been here that long and couldn't find a search function.