Free bets can look straightforward until you check what happens to the stake....

https://mighty-wiki.win/index.php/How_can_I_tell_if_a_betting_site_is_licensed_for_Irish_customers%3F

Free bets can look straightforward until you check what happens to the stake. This guide for Irish customers explains the key terms, how to compare offers and why a €10 free bet at 4/1 returns €40 in winnings when the stake isn’t returned