It’s crucial to find a company that wins with its customers and suppliers. Otherwise it runs in the risk of incurring wrath from them.
If customers turns against you, you run the risk of depriving yourself of income streams. Look at Valeant and potentially Transdigm. They acquire companies that own monopolistic products and jack up the prices of the products after the acquisition. This corroborates with Citron Research view in its short report.
If your supplier turns against you, your cogs might increase, or you get lousier credit terms, or worse, you are held hostage if they refuse to supply you.
At the end of the day increasing your profit margins just because you can builds your company on a shaky platform.