Back in the day, your calling options were limited and generally quite expensive. As for calling abroad, well just forget it unless you’re rich. Now days with the advancement of voice over ip (VOIP) like Skype and call cards which essentially route your regular plain old telephone (POTS) call over voip backends, you can call worldwide very cheap.
Low dial plans exist and you should be using them, there’s really no excuse to be routing those expensive calls through your regular phone line!