[edit]Deleted because the point isn't getting across and I don't want to argue the point.

I don't think it's a hard-and-fast rule. Apostrophes can be used for abbreviations in order to clarify that the S is not part of the abbreviation or if it makes the abbreviation otherwise weird to read.
Either way I don't think a personal pet peeve is an issue that needs to be addressed by Subeta as a website. This seems more like something that belongs in the Bragging & Complaining forum?
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From whatever result I tapped on from google