As you can see from the extract from the Citizens Information Website below, you must fill in an application in order to be included on the Electoral Register.
I cant see why a Local Authority would include someone without receiving an instruction to do so first.
As per your second question about data protection, you can opt out of direct marketing if you so wish.
The Register of Electors
Every local authority in Ireland is responsible for compiling and publishing a list of voters in its area. This is called the Register of Electors or the Electoral Register. Anyone can inspect this Register and it is available in all
local authority offices, post offices, Garda stations and
public libraries. You can
check the Electoral Register online here.
The published Register contains the voter's name, address, polling station and category of voter. For inclusion in the Register of Electors you must complete
application form RFA which is available from your local authority, to whom it must be returned.
A new draft Register is compiled each year and is published on 1 November.
The Electoral Register and direct marketing
Local authorities publish two versions of the Register of Electors: the full register and the edited register.
The
Full Register lists everyone who is entitled to vote. Once a Full Register has been published, it can only be used for an electoral or other statutory purpose.
The
Edited Register contains the names and addresses of those voters who have indicated that their details can be used for other purposes (for example, for direct marketing use by a commercial company or other organisation).
If you do
not want your details to be included in the Edited Register, you should tick the "opt out" box on the registration form. If you want your details to be included in the Edited Register, that is, you are happy that commercial companies and other organisations will contact you with direct marketing, you should leave the "opt out" box blank.
If you do not tick the "opt out" box, it is assumed that you want your details to be included in the Edited Register, if you do not wish your details to appear on the Edited Register tick the "opt out" box.
It is an offence for an organisation/commercial body to contact someone from the full electoral register for direct marketing purposes. This was set down in law under
Section 32 of the
Electoral (Amendment) Act 2001. Find out more about
how to deal with unsolicited direct marketing material in Ireland.