Well, probably because it's already illegal to do that.
"No offensive player may: (a) pull a runner in any direction at any time; or (b) use interlocking interference, by grasping a teammate or by using his hands or arms to encircle the body of a teammate; or (c) trip an opponent; or (d) push or throw his body against a teammate to aid him in an attempt to obstruct an opponent or to recover a loose ball."
Rule 12, Section 1, Article 4,