What you were expecting to happen, and what actually happened?
I was expecting to not get common cards and got them. My guild has over 20.000 seals (I checked before buying the chests), which is supposed to give you only rares and up… and I still got a bunch of guardians. What the hell man 
all chests contain guardians until you have 4 copes of all 6 at mythic rarity.
But you won’t get any non-guardian commons.
Ah, so that’s why I only got guardians. Still kinda lame but oh well. Overall I’m really unimpressed with guild chests, I have to admit. Anyway, thanks for clearing it up
Guardians are, in my opinion, the main rewards from the chests. When you get them traited and sufficiently ascended, they have potential on a few teams. Since guild chests are the only way to gain enough to ascend them, they’re useful as a resource in that way, with the potential bonus of getting a legendary or higher.
And keep in mind, you will need a lot of guardians for the last 2 ascensions. Collecting 100 of something isn’t quite as Skinner-box gratifying as getting one really rare thing, but you’re still making progress.
I was also clearly promised no commons. Someone told me once you get all of the guardian troops to mythic, that will stop. Guess what, it didn’t stop. Once you get all of the guardian troops to mythic, you should not have to put up with getting any guardians in your guild chests. This is both misleading and disappointing.
Once you get all 6 guardians to Mythic and 4 copies of each, they will stop and Guild Chests will be exactly equivalent to Glory chests (at level 5) or Gem chests (at level 6).
This may change when the current Guild Wars troops get rolled into (presumably Guild) chests, but we haven’t had any solid confirmation of when or exactly how that will work.