The correct answer to this open question is the following.
You forgot to mention the historic period in time or further reference or the kind of businesses you are referring to. However, it seems that you are referring to the Gilded Age. If that is the case, then we can comment on the following.
Business structures such as corporations, pools, trusts, and holding companies led to the elimination of competition between businesses because the large companies started to buy their competitors and integrated horizontally to the extent that they became monopolies.
We are talking about the cases of the Standard Oil Company that belonged to John F. Rockefeller and the Steel Company that belonged to Angres Carnegie.
The impact on consumers and workers was that consumers could not have enough options to choose from. They had to pay the price as it was without any other options. Workers labored under unhealthy and dangerous conditions, working for long hours with low salaries.