But no one would spec leather electric seats in a TCR!!
I would.
but I'm not a badge snob
The thing is though your point is your subjective view on "value" as an argument, it's not really about being a badge snob. When I sat inside a SEAT, my subjective view was the quality of the materials, fixtures & finish, equipment levels etc was inferior in so many places that matter to me. It didn't, for me, feel as nice a place to be as the Golf, it didn't feel special enough. The GTI brand is also strong, it's a brand I like and can relate too, that is reflected in the residual values of both cars.
Sure the SEAT is cheaper, but it's cheaper for a reason, because it's built to cheaper margins. That's not to say VW don't build the Golf to margins, but those margins are different to SEAT margins.
I'm also not saying I'm right, that's just my view. SEAT exists for a specific target audience, I am not in that target, but that's not to say I'm wrong for choosing the Golf over the SEAT. I just don't personally see the SEAT as good "value", I see it as a cheaper alternative. Ironically, from personal experience having sat in a new Superb recently, I rank the Skoda product higher than SEAT.