This is ridiculous!

Welcome to EA's RNG unlock system, where you're almost never guaranteed to get what you want whenever you want it. 

Blame EA. Like all corporations, their rampant greed has no limit. It is this avarice that causes them to try and get as much money from us as possible, and is also why they don't spend any of it on their atrocious servers. Because of EA no doubt Mass Effect Andromeda will have day one paid DLC, and no doubt it will be central to the main storyline. Take Leviathan for example: this paid DLC revealed the origins of all that was happening in the Mass Effect trilogy. It was essential information to the storyline...and EA held it back deliberately so that they could fleece the players further. A truly disgusting practice. The worst thing Popcap ever did was throw their lot in with these villainous, parasitic scum.

Not just Leviathan either, but From Ashes as well, which provided a huge new perspective on the lore of the series. Both DLC's that provided a huge chunk of lore to the series that was central to the story, left out, since From Ashes was Day 1 DLC, but I got the Collector's Edition, so that didn't bother me. The RNG unlock system for the multiplayer did bother me though and it still bothers me to this day. 

It honestly really is a filthy, avaricious practice, whereas a more straightforward system would actually be more pertinent. At least Popcap is taking strides to go against this trend by using Rux as a bypass for this system. 

I found that the best way to get an item you want is to select the pack that is best for your item (say you want a non dlc plant customization, then you go to the fertilizer fun pack) then just spam that pack over and over until you get what you want.  I got the Disco Chomper that way.