Erm, I've never received so little holiday, even when I worked low paid manual work.

Currently I get 25 days per year not including 6 days stat, for 31 days total or just over 6 weeks total. This is considered average for London and the UK, I would consider 5 weeks to be the absolute low end in the UK. At the upper end in London the news about the Tube Drivers strike disclosed that they have 40+ days holiday, which is just over 8 weeks.

When I lived in Sweden the numbers were higher, with it being compulsory to take a fortnight in a contiguous block in the summer. The UK is the worst of the lot, and we have it OK.

Just my experience, but it varies so greatly from what you're quoting that I felt obliged to respond.