I'll break it down for you.
I base it on your numbers (destroy a 168000 finca with 4 missile shots).
168000/4 = 42000 and 168000/3 = 56000 so the players you are referring to have a missile damage in the 42000 - 55999 range.
If they were to take out a 270000 finca with 5 missile shots (which is probably around the maximum number of shots you can get without gaining energy), they would need at least 54000 damage/missile (= 270000/5).
Among the given range (42000-55999), players who have at least 54000 damage/missile amount to 14,3%. That is provided the progression curve is linear, which might not be the case but is likely close to the reality. Calculation is as follows:
55999 - 42000 = 13999
55999 - 54000 = 1999
1999 / 13999 = 14,3%
You would have to define "normal player" and "spend much" because these could have very different meanings in different people's minds. I don't have access to the subscription offer. I consider myself a "normal" adult player: I buy gold around twice a month, which roughly amounts to a handphone plan.
You seem to always have something to complain about, but I don't quite understand what exactly is your concern.