The difference being is that actual items, not consumables, are investments. You spent a lot of gold for them to increase your stats and provide the unique abilities. These unique abilities, however, are attached to the stat sticks which makes them more selective in who can use them, who will use them, and whether or not it's a good option at the time.

The problem with offensive consumables, or at least the ones you're conceptualizing, is that they're abilities that are previously only on champions or a select few items that have their high cost and stats to justify why they can exist.

A smoke bomb consumable is just stupid strong. It's part of the reason Graves is as strong as he is. Properly placed smoke bombs make or break ganks, skirmishes, and team fights.

We can certainly use more interesting consumables, but because they're consumables, they need to be accessible in price, and ones that provide an ability need to be balanced in whether or not it's worth a slot to hold them versus how powerful they could be early.

Given how income works in the game and the average gold a player holds on to at any one time (Rarely more than 1500-2000 at the most, as items / recipes don't tend to extend beyond that), even a powerful consumable probably wouldn't price above 500; And if the effect is strong enough, you pay 500g to win a team fight and that burden is more than likely being shifted to the Jungler or the Support, and none of them will love you for it.

It's a difficult area.

what if you put the items in dominion, gold income is not as much of a problem there so gold investments are less consequential, u would be choosing stats or 1 time burst items to win a fight and get a cap point

Once again not these exact items with these exact stats at these exact prices

I don't pretend to be an expert in balancing games but I was trying to identify an area where more could be done.

Aside from what other people have said, adding these items would add a secondary range to every champion in the game. What happens to champions like Fiora who are purely melee and have no escape? They're invalidated even more than they already are. Imagine your annoyance as that Gangplank you once countered just repeatedly throws poison or knives at you from range while paying for these items with the extra money he got farming with his Q he would have had to use if he wanted to harass you without these items..

The issue with items like this is you have to balance the entire game around them, and why do that when it's hard to tell if it would even have a positive effect?