Just how many bots are there in lower-level matchmaking?

So, I started leveling a couple new accounts recently (because I decided it was absolutely necessary to have a duo account set named "Donkey" and "Kong", each used only for Soraka, and Wukong, respectively) and have discovered a rather disturbing trend in all the aram games I've played on these accounts.

So, first off, I'm ASSUMING matchmaking is designed to match players at similar levels. And that therefore, for the first time in eons, I'm being matched with lower level players. Possibly noobies. That's just fine, I don't care if I get into a game and Nasus doesn't even know what q-farming is. Everyone learns at their own pace.

But it seems that in EVERY aram, there's about 2-5 players (yes, THAT many), who move very little, seem to auto without ability use half the time, find a target and then stay on it regardless of their health levels, and, well, pretty much everyone goes, "yep, those are bots".

Which means about a THIRD of the pre-level-30 matchmaking pool consists of bots, probably hacker nerds auto-farming lvl 30 accounts. Heck, I just ran across a site selling lvl 30 accounts when I googled speed-leveling tricks for League. Really? Does Rito just let this run rampant?

I don't know about MOBAs, but in every MMO community I've seen, when bot farming becomes an issue, the devs break out the banhammer, and, very shortly, the issue evaporates. Why, in such a well-established game, is there such a ridiculous amount of bot farming?

WHAT'S GOING ON HERE PEOPLE! I DON'T UNDERSTAND!

Let me know your thoughts. Comments, objections, and insults are welcome.

P.S. No I don't actually own "Donkey" or "Kong". Those were, not surprisingly, taken. But I found a close enough compromise by adding a tag alluding to peanut butter jelly time. Almost as good, possibly better.

Double P.S. If you own either of these names, please give them to me now >:(