Inactive bases are not so much removed, but sinking, like a ship taking on water. With each raid, they usually lose trophies, either a little, from people getting 50%+ and being much higher in cups than the base, or a large amount, from people much lower and raiding it for 100% damage. Rarely do they gain trophies, and keep them afloat longer, but eventually they will sink to the sub 200 cup level, and become sunken treasures for people willing to dive down to get it.
Reason why you don't see many in higher Leagues is because they don't have far to fall to drop out of sight from that range, and sink through the ranks past the other Leagues, until they hit buttom, or get removed by SC.
I can actually see why SC has an interest in removing such bases, since abandoned bases are just 'sugar rush' rewards; getting huge rewards for minimal effort in raiding, all because you are willing to hit the [Next] button often enough to find it. It is poisonous to gameplay as people get used to such rewards, while getting bored with using the simple tactics to get the reward, then either complain about not finding enough loot when those bases with 'low hanging fruit' are gone, or complain about the game being boring. The complaint about it being boring is both true and false, since you can always use more interesting armies to bust into different bases, but the incentive to do that is lacking.
And yes, as you can tell in my signature, I don't run very complex army builds, and I do loot farm. To put it in context of a real life problem, 'just because I'm a smoker too, it doesn't mean I'm a hypocrite for complaining about people smoking. It is just hard to quit.' (I don't smoke, but the concept is the same. I wish I ran more advanced stuff, but I don't)

