There is the way to download files from such servers using browser.
You may copy link, paste it into address bar and add login (and password, if needed) before server name, delimiting it from server name by '@' symbol.
E.g. original (anonymous) URL is: ftp://ftp.server.com/file.zip
Non-anonymous URL looks like: ftp://login@ftp.server.com/file.zip, or, if password is used, ftp://login:password@ftp.server.com/file.zip