Actually, it may just be a cost cutting tactic; some services have dedicated subtitle 'channels' to serve particular purposes; there is the usual straight ST where its just the straight text of the dialog, and there is also the ST designed for the hearing impaired, commonly known as "Closed Captioning" where the ST also includes descriptions of the ambient sounds and other audible aspects, such as soundtrack musical cues, in addition to the ST text; I have noticed a few instances where the two are mixed, such as you describe, and I wonder if the streaming services may be taking a shortcut in an attempt to cut the costs of having to create two separate formats, no to mention the savings in bandwidth utilization...
<O>
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