They don’t need to ask for money and even if entry is free and they are giving it away it still falls under regulations that they need to follow.
It’s why in giveaways there usually a list of places that are exempt when giving free physical items away. Even at mmorpg.com when they host a giveaway from headphones or game copies etc there a list of rules and place that are eligible and not.
About the only time there isn’t a list of rules and place that are exempt is when they are giving away codes or beta key since those are non physical items that can’t really be tracked.
From what I can see though this is for a 50% off coupon or code so it probably no worries.