I had to check on this. Loake has half insole with writing on it. After that seems to be leather with a leather stamp visible. Trickers similar. Crockett and Jones handgrade the insole extends the length of the shoe.
It does not bother me and I never gave it much thought.
This is my Loake 1880 Suede Oxford Radleys with embossed leather.
My Loake Shoemaker dark brown Oxford with some sort of suede. This feels really uncomfortable especially with ultra fine socks.