Irish local authority bye-laws do not apply to private land.
The law of contract which is something that has been developed over hundreds of years applies in private situations.
Sorry to tell you that most civil conventions are still based on best practice developed by the British.
Any person can get a name and address from the VRO on payment of a fee. The didn't get the drivers name get got the owners name. Good luck to them getting the drivers name.
Any disabled bays painted on private land have no force in law. Whilst it may be morally wrong, it is not illegal to ignore them.
I hate this typically Irish attitude that because someone puts up a sign in a private carpark saying you must pay €80 etc then it must be legal and pay up. It is time that people realise it is a scam. These charges have no legal backing. It would be no more legal than me putting up a sign outside my house saying you agree to pay me €100 to park there. Would you pay? Of course you wouldn't. There is no difference except a sign is put up by Tesco/Dunnes/Euro Car parks, that does not make any more legitimate.
I dispair at times with the irish attitude.