Ehm, some of them are African wines, some from Argentine. My mother is a teacher at the waitress/cook department and because of that we get a lot of wine when they get rid of the old shipment. Most are around 8% and only a few are 12,5%. I know for certain that wine doesn't go over 12,5% but Mead can go over 14%. It's brewed differently and is mostly stronger than wine.
or maybe Dutch folks just don't sell wine that goes over that limit. But my teacher said that 12,5% is considered strong for a wine while it's considered weak for Mead.
Scroll down to wine:
http://en.wikipedia.org/wiki/Alcohol_by_volume
"Wine 9%–16% (most often 12.5%–14.5%)"
Right above it is mead, which is maxes around 16% also. They are made essentially the same way. It all depends on the type of yeast you use, the nutrients you give it, and how much food it has (sugar). I had a mead made with Champagne yeast (which is very hardy and can survive in very high alcohol conditions, which is why Champagne is higher alcohol than most wine, the yeast continues to consume sugar long after the environment would be toxic to many other yeasts) and it was around 18% abv... it tasted a lot like Champagne and it was bad.
Mead does have a dry to sweet scale. Many people will let mead go for a first fermentation and then add additional honey. This will reactive the yeast and produce a higher alcohol percentage. However, typically, there will be more sugar left over than after the initial fermentation, leaving behind a higher sugar content, and a sweeter mead. My brother has made some fairly dry mead before. It's not bad, though I prefer somewhere in the middle. Not cloyingly sweet, but not entirely dry either. Fruit based meads are fantastic. I especially like blueberry meads.