I did have been read article on Wikipedia that in Kyokushin karate they do not use throwing or gripping or any kind of locking technique to practice or to use. which kind of philosophy is stays behind this?
Every style of martial art is unique from all others. Kyokushin, like all fighting sports, is no different: there are certain rules about their sport that make it stand out from all other sports. Their rules are their niche.
Having said that, all styles of martial arts - unless they are new - are systems complete with all kinds of fighting, defensive, and control techniques. In the case of Kyokushin sport fighting, they have subtracted out some things such as grappling and throwing, as you pointed out. But that is just the sport aspect. The style itself is complete, and generally has a more complete repertoire of techniques. It may be the case that your school/instructor does not teach (or does not know) that aspect of your style - that is a common phenomenon in all styles.
To give you an overall picture of the state of fighting sports in general, take a look at, say, Wu Shu, or Shotokan Karate. Both are martial arts styles in their own right; are classical styles; and each are known to have a very complete repertoire of techniques, including striking, kicking, throwing, pins, locks, chokes, gouges, and weapons. One may counter your original question by asking: Why do these styles - known to have weapons - never compete with weapons? Some may argue that they do - but only via forms (kata or taolu). Others argue it's too dangerous - but would not explain European fighting which DO use weapons in fighting sports. The overall answer is this: the styles have weapons, and their practitioners are no doubt familiar with many of the weapons their styles traditionally use; but for whatever reason, they choose not to use them for competition. Whether it is because of popularity, insurance, safety, timing, quality instruction, legalities of training with such weapons, similarity to another sport, or some other reason or combination of reasons therein, that is known only to the sport body governing that style or particular competition instance.
I would also caution about what you read from Wikipedia. It's a great resource to have, especially if the author(s) cite their references. Your best bet is to go directly to the body which governs a particular tournament or style. From there, you can read their rules, and if you so incline, you can ask them why such rules are in place.
In all honesty, I tried to do just that for you, and unfortunately came across some verbiage which clearly indicates petty infighting between federations. For example, this one, especially about half-way down:
And then there's this one comparing itself to "others", also about half-way down:
...and on it goes, there are many federations, and all pointing fingers at each other (or maybe perhaps at a few; it's hard to tell, and I'm not part of that milieu of politics). Nevertheless, the rules governing sport are very similar, and, the components which make up the style (including kata used by other Karate styles) are also pervasive. Therefore, your style isn't old, but it derives from very old styles, and still, is very complete. What you may lack is quality instruction. We in Taekwondo see this all the time, and often have to resort to joining Karate schools with emphasis on kata, bunkai, and oyo in order to help learn what we do, when local TKD instruction lacks in this area (although they may excel when it comes to competition).