Consumerable Active Items for combat - Why is this not a thing yet?

And I'm talking about combat oriented items and no hp pots or sightstone. These can work as one time uses or on a chrage system, that's balancing details we don't need to bother with right now. Charges would refil on returning on base or if something specific happens (kill, tower down, etc.)

Just some random thoughts I came up with:

1.) Smokescreen. Upon activation creates a smokescreen at your position (think of a bigger graves W with no slow) that denies vision and grants a short decaying speed boost.

2.) Protective Charm. Upon activation shoves all hostile units a tiny bit away from you.

Of course one could also use simple damage mechanics for this:

3.) Alchemic Firebomb: lobs a projectile at a location that deal inital damage and causes the area to burn for a few seconds, dealing damage to all units that walk over it.

Or completly weird stuff like this:

4.) Zaunite Terrain Disorter 9000 (Patent pending): temporarely deletes a small area of terrain so it might be transversed by players. I have no clue if that would work with the code tho.

I rember stuff like these from several WC3 funmaps that were somewhat dota-like (back in the old times where there was no LoL ^^) and it always allowed quite impressive and daring tactics. You pretty much sacrificed one of your item slots for an extra ability that was useful, but not to be used indefinitely. However, when used right these could be game turners.

On top of that it could make the early game quite interesting. Why start off with something lame as a dorans item when you might as well try to take something like this to gain an edge over your opponent?