The original Fast Track advertised free Capsules. They gave them away the second one as well, but it wasn't as advertised because SGi assumed most people remembered how the first one worked.
It's a courtesy gift of 'Hey, you might have full slots, so here's this so you can freeze something you might not play anymore to Fast Track something you want to try'
I didn't even log in, I froze something ASAP to Fast Track a Gambler on my main.
Diablo III North America Glacea#1307
League of Legends Queen Nimera, Level 20
New Leaf/Pokemon XY 4511 - 0825 - 1589