May I ask who is holding the funds? I guess the goal is to raise more money then is being given away, which is quite a lot for a new service.
Using a multisig wallet with an escrow that needs to sign off would give a lot more trust I guess.
CryptoEbe - May I know why you ignored the above question to answer?
It is a valid question and it is quite a huge amount why can't you choose some trusted members as an escrow for the funds? If you do that then you may find many real ticket buyers otherwise you need to struggle even to sell free tickets because I don't want to waste my ticket to register an account and to claim that free ticket when I'm not confident about your system.