It is like that for technical and gameplay reasons. Do you know how frustrating it would be to players if anything you knock around just fly off and be lost forever? It would make any kind of salvaging or building in space impossible. Same would apply to ships if you end up leaving them and they just fly to nowhere leaving you stranded. Lastly, the game would bug down a lot keeping track of objects moving around, especially if said objects are just lost, never to be found by players again.
Friction could be toned down a bit for sure, but it needs to remain to keep it playable for most players.