As title says this is very smart since around '08-09 the Big Blizzard Bear was introduced. This implementation through the paid Blizzcon ticket system will not undermine current players that have got it from back in the day since it doesn’t transfer over to Wrath Classic.
This also incentivizes players like me who doesn’t have much of an interest in the Blizzcon event to buy myself a ticket 
Please do bring the BBB back, it’s really cool!