Because you can open a private/incognito/porn tab and view the same article without actually paying for it, and a premium should offer you something worth a con

Because you can open a private/incognito/porn tab and view the same article without actually paying for it, and a premium should offer you something worth a constant amount of money draining from your account. Paying 15 euros per month to get a daily crossword + cooking section (or 9 euros per month to not get them) is something not a lot of people are interested in.