I agree with the one vote per parcel rule, rather than having a couple voting twice for one parcel and possibly canceling each other's votes. That's not the issue here. Also, the issue here is not with someone buying an adjacent lot to have extra privacy. Again, I agree that those lots should be combined and count as one parcel.
The big issue here is when a developer either buys several lots (which may or may not be side by side,) or else buys one huge lot and divides it up into multiple small lots with the intent to sell them off one at a time. Maybe he does sell some, but still owns the rest, some of which no longer touch each other. If a person bought two house lots in different parts of the subdivision, they would be charged for two lots, but that doesn't work as well when a person buys one piece of land and divides it into half a dozen or more undeveloped lots.
We had this happen in our road association. If we had counted each of the developer's subdivided lots as a separate parcel, he would have had to pay 12 assessments. Since he never paid anything until he sold a lot, we figured our chances of collecting multiple assessments from him annually were zero. By counting all of the land owned by that owner as one parcel, we were able to collect back dues from a few years on one parcel each time he sold a lot. The new owner of that lot would then pay each year, and the developer would again be billed for one parcel for all of what he had left. When he sold another lot, he would again pay what he owed for one lot since the last time he sold a lot. By the time he sold the last lot, we were getting paid for all twelve lots by the new owners.
The other issue is that if we had billed him for each of the twelve lots separately, we would have also had to give him one vote per parcel. Since we had trouble getting more than a dozen people to show up for Annual meeting, he could have outvoted the rest of them. So the logical solution was to consider that he was the owner of a single parcel, charge him one assessment, and give him one vote.