I know you like to think your Primark jeans are as good as £110 nudie jeans, but here's the facts.
Your Primark jeans are not cheap because they're from Primark.
They're cheap because they're ****. They're in Primark because they're ****.
They're made of bad denim, they're badly cut and badly made.
Don't get me wrong, you couldn't pay me enough to have G-STAR RAW DENIM printed on my leg, it's not going to happen. I also wear lots of cheap clothes.
But you pays your money...
On to the OP... shop in smaller shops, shop online, there's plenty of stuff that's either got very little or no branding on it, or has branding on it that's not so common. Get a little more independent, or wear less-known brands. That's it. You don't have to wear Bench or G-Star or Henleys, not all designer labels are in three inch high lettering.
For example, Carhartt make lovely jeans. They're not stupid money and for the most part the branding is a 1 inch square label on the back pocket.