I've noticed that Thomas Müller of Germany wears very small shin guards (at least most of the time). If I remember correctly he did the same thing during the last world cup or Euros. I played a bit of soccer when I was young and can't understand why a professional player would refuse to wear shin guards that cover all their shins. They are the only thing that keep you away from seriously hurting your shins and going through ridiculous pain. So what's the reason behind this? Why would you leave a considerable amount of your shins unprotected and risk getting injured??
The most important reason: It's simply a question of style. Like Cristiano Ronaldo wears long socks, some others are wearing sweatbands, ...
Besides, it's not very comfortable to wear shin guards. One sweats heavily underneath them. In personal, because of this reason, I'm wearing my shin guards only during the game. Never during training, warm-up or even a training match.
In addition, most injuries around the shin guards take place lower (ankle) or above them (knee).
I play with the smallest possible shin pads. i don't like any padding around my ankle. as a striker i need to have a clean hit of the ball. I find with ankle protection that doesn't always happen. Being a striker means most of my injuries from fouls are down the back of my calve where even large shin pads won't protect me. Its nothing to do with bad habits, more so to do with the position you play. It does also help if you know how to avoid a nasty tackle.
Shinguards came about because soccer used to be played literally with boots, big huge things, and the preferred method of kicking the ball was with the toe. If you missed, you kicked the shins. That changed in about 1950 with the introduction of modern shoes like they use today.
Today at anything above fourteen years old it is rare to see a direct hit to the shin. As an adult I've personally taken a kick to many a bare shin and not been any worse off. Shinguards are sort of useless. It stings but its almost impossible to break a shin. I am much more worried about my ankles and I wear ankle protectors. Today we still require shinguards as a nod to safety, but they are more ceremonial than not. This is stated in a soccer book I read, I forget which one (I think maybe "The soccer book" http://www.amazon.com/The-Soccer-Book-Sport-Tactics/dp/B003R4ZG46).
The light, tiny 'slip in' shinguards are used because they are exactly that, light and small and unlikely to interfere with movement.
I've been coaching for 12 years now.
I have played soccer for more than 20 years, since I was kid my parents tought me to use shinguards. This will be the first equipment they bought me.
Sometimes I have forgotten to use or in a hurry, and have received injuries like fissures/small fracture for bone and muscle in the shin area.
Last time I was injured, after doing a legal slide tackle, a team mate stepped over the side of my shin with his bodyweight resulting in my lateral shin got fisured, I was wearing decent shinguards but received impact on least protected side and some plastic cleats made direct contact to my leg. After this injury I will get an elite protective shinguard model Diadora Gamma Carbonio, which is the model made for Francesco Totti after he received serious injury bone fracture prior to 2006 World Cup. (Price $150 not more expensive than a cast at hospital and more than a month without playing! Medical bill less complicated fracture = $2500 if surgery required = $35000 + )
Francesco Toti minute 5:18 someone steps on his leg World Cup 2006 just after fracture comeback , 6:18 he is fine and shows his new specially designed Diadora shinguards. https://www.youtube.com/watch?v=DXNpNHvZWv0
Why do some pro players use such small shinguards, same reason amateur players either dont use or use small shinguards. They have acquired a BAD HABBIT . Fifa doesnt regulate the size of the shinguard. Its true with time and small hits bone gets more resistant, but some hard hits or players steping on your leg are very dangerous.
I think there should be more strict rules on the size of shinguards worn, even though maybe some will say more protection can result in more rough dangerous play, like NFL American football for example, but the shin is a very sensible area, even without fracture injury a hit on an exposed area can get you out for the rest of the game.
Even if you yourself while kicking hit accidentaly another player with your shin, you can easily get injured. I have seen broken shins while in Karate practice and tournament for example a guy kicked, amd opponent raised elbow to protect, resulting in fractured leg. OUCH Horrible injury to watch.
I have learned my lesson , I dont play nor train without appropiate shinguards . For me a well designed and securely fit shinguard ain't uncomfortable at all, I also like to use classic leather shoes. I run very fast I dont care if I have and extra pound on my legs, you must be faster than me to catch me. ;)
P.S. I am also an amateur "semipro" long distance runner. 5K - 17 minutes