Can you explain to me how Sona is in 20% of ARAM games?

Aram only accounts, people only buy the "aram op" champs on them.

There are accounts that only own champs like Sona, Lux, Zyra, Brand, Varus and other longer ranged champs just for aram since they dont have to worry about picks like Trundle, Udyr and other champs who have a harder time getting in against longer ranged targets.

Because the champ pool for aram is what is available for you to lock in (so what you own + free to play), so mostly you're facing ARAM only accounts where they only buy like Sona, Varus, and Ziggs. This lets them get the champions they want a disproportionate amount of the time.

complain about it too much and it will go the way of dominion... >.>

Well thats very simple to answer. She is in 20% of the aram games, simply because people play her 20% of the time. Glad i can clear that up for you toodle loo

15% chance she will be played per game. Add in rerolls and ARAM only accounts and you can raise that bar significantly.

shes free thats why. It always happens during free week. Kinda irritated seeing all these sonas because im a sona main an i only get her like once a year in aram :/