Another option, if you don't mind allowing people to download the full resolution photos (usually OK if it's just photos for friends/family) is to use the Tools -> This Gallery -> Download All option to generate a download URL. You can only pick that command yourself, while you're logged in, and it will e-mail you a URL to download a ZIP file of the entire gallery. You could then put that URL in the album description to allow easy bulk downloading.
Keep in mind that the download URL expires after two weeks, so everyone either needs to download quickly or you have to generate a new URL (run the command again and update the link) if you need it to work for longer.