Why would that be stupid? I actually think it's kind of stupid for only one country to have the bridges shown on EU currency.

I was just thinking it would be cool if a bunch of the EU countries each started building these bridges. You could see it as a symbol of unity. Maybe they could do something interesting with it like each country adding their own personal touches to the design. Or using the bridges to bring attention to lesser-known, interesting cities in the country.

Actually at least in France the cathedrals became taller and taller exactly for that reason.