Well, I do remember the case of that one guy who built his own sailing boat back in the garden and got deported (Phuket a decade ago or so) That was also his "hobby" 😉
Of course there is one and this is the only one you should use in order to be sure you have a genuine and fully refundable ticket. Thai railway offers a 100% refund up to 24 hrs before travel. After that it's 50% and the latest time you can get a refund is 4 hrs before departure time.
12go is a third party reseller who offers no added value whatsoever.