Thanks for your advice girls I don't thing any shop in Spain offers the brands you told me about though, and I'm SUPER reticent about shopping online -I'll get there some day, I know, but I'm just not ready yet lol-. However, Spain is well known for its shoemakers -Camper or Wonders, for instance-. I've had them both, no luck. I mean, they are fine, way better than anything from Zara or idk, Payless, but not good enough to make it into 8-hour shoes. Clarks are just a pure disaster on my feet -I have four pairs of super expensive Clarks and the four of them torture my feet-. So I've really got fed up of very expensive shoes. Nowadays I try to buy cheaper yet well made Spanish/Italian shoes that maybe are not so fashion-forward but are comfier in the long run. They are usually made of soft leather and I try to find them with cushioning on the sole -except for the gladiators. I used to be very happy with my gladiators before my feet got even more problematic.
chewyspaghetti- I've tried silicone insoles, no luck with them, and they rub my skin even with socks on -I've tried them for high-heeled closed shoes-. Besides, insoles on totally flat shoes would only make it worse, I think. Blister block stick doesn't work on me either!
Diana- I've tried moleskin too, and it has worked for some pairs. I'm addicted to Compeed, but oh my, aren't those expensive!
Journey - A chiropractor might be a good idea, but idk... I already know -told by a doctor and a physiotherapist that I have a tendency for bunions -even though I don't wear high-heels nor pointy shoes, go figure- and that I don't have much cushioning on the foot-bed, which leads to the inflammation of the sesamoid bone. So basically he told me to wear flat not pointy shoes, and that's what I do... most of the time.
I know, I'm hard! If it is of any help, I don't go complaining to people when my feet hurt, I just eat it up and stay strong lol