Overall, they do seem very similar. Especially between the HoC lines of kilt hose and shooting socks.

But it occurs to me that when compared with other brands of kilt hose (not HoC), the turndowns on shooting socks tend to be much longer than regular traditional kilt hose. For a visual example, here is a photo from the thread about the Duke of Edinburgh attending a Highland Games with the Queen and the Duke of Rothesay. Note the difference between the turndowns on their hose. The Duke of Edinburgh's hose are more like traditional standard kilt hose, where the Duke of Rothesay tends to wear checkered-top hose that are more like shooting socks.



What I've noticed is that HoC's turndowns on their kilt hose tend to be longer like shooting socks, where other makers tend to stick with a shorter turndown. I love the quality of HoC hose, and they are by far my favourite brand of kilt hose (aside from my custom hand-knit hose), but I rather dislike the fact that the turndowns are so long, because they look like shooting socks to me.

And on the same line of thinking, I believe shooting socks are intended to be worn a little higher than kilt hose (as others have mentioned). The top of a shooting sock comes up to just below the knee, where kilt hose should be a couple of inches below the knee (or three finger widths, as a general rule). Again, HoC makes their kilt hose more like shooting socks, making it difficult to stick with this general rule.

So for me, that's usually the glaringly obvious difference. Overall height and the length of the turndown. Does it work? Yes. But I do notice the difference.