I think you start with like 100 TBT! But I also think a lot of junior members clicked that thread today to get the free 50 TBT Just my thoughts. Might be wrong.
Also the first couple of times that a newbie posts, those posts earn them a large amount of TBT bells. After that it goes back to the regular amount, if I remember correctly.
That's been done before and we usually take away the bells given to the main account/take away items purchased with the non legit earned bells. People who make alt accounts for bell swapping may also receive a warning for the first offense and infractions for each subsequent alt account.