Late to the party, and seldom post, so forgive me if my comments are out of place or unwelcome.
I find value in a knife, or a tool, or any other inanimate object, based first on function, then on aesthetics. I'd be lying if I said that appearances were irrelevant. They used to be higher on the priority scale, but at some point the scale flipped and I know only own things I really need or use. That's just me, and it's partially based on frugality and income. I don't think it's a virtue, or a better perspective than others. Just is.
All that being said, the aesthetics of an object and whether I find it appealing to the eye are now more based on how useful and functional that object is. Really useful is really attractive and really useless is really unattractive. I can appreciate the "lines" of some knives for a short time, while feeling that they are useless and having no real desire to own or handle them. Usually, I quickly end up feeling like the object is shallow, pointless and vain. Sort of like modern art. Sometimes one of those amorphous blobs of concrete or steel will really catch my attention and hold it for a few minutes, but in the end the overarching question for me is "what's the point?", and I walk away. That sort of scenario has occurred for me with regards to tactical knives. I love to carve, cut up food for cooking, do basic bush-craft tasks, and use a knife for the dozens of tasks I encounter each day that are suited to using a knife for. For me, none of those tasks involve a tactical scenario. Never have, and I hope they never will. As a result, I feel zero draw to tactical knives. If I were in the military I would probably value these knives' functional beauty, but I have no real use for them. I've given all of my tactical stuff away and just have a few puukkos, general utility knives, and choppers for heavier chores. None of these knives are real "lookers" but I could not appreciate the beauty of their form more if they were damascus steel, engraved and embellished museum pieces. Their beauty, in my eyes, is how well their form is suited to their function, and that they are devoid of embellishments that would not benefit their function.
I don't think that there needs to be a "point" to a knife, or watch, or whatever, to justify someone valuing it. That's not my business, and I am glad for those who have the income to indulge a desire to collect or who place a higher value on price, pure aesthetics, or engineering. Each person has their own perspective as well as their own list of required "functions", and if the main function is to look and feel nice - with no other use, that's fine. Just not my flavor.
If you like it, and can afford it, what other justification do you really need. Buying anything to impress others is a form of slavery.