Trevor, I always appreciate your correction to my essay.^^ I would like to ask you a grammatical question. I used prepositional phrases with gerund in two underlined sentences as below. I believe they do not have fallacy of grammar and assume it is a difference of nuance. Could you explain why 'to infinitive' is better in the context? 

Some people may argue that Businesses are encouraged to do whatever they can do make a profit, because corporates are profit-oriented. I, however, am against the idea that companies can participate in every activity for gaining return.

I, however, am against the idea that companies can participate in any activity to gain returns

 The reasons for this are that businesses cannot violate certain laws, even if they are losing money, and that corporates have a moral obligation to conduct themselves in an ethical manner.

To start with, businesses cannot engage in illegal activities despite some loss. In other words, a business cannot defraud its clients or shareholders simply because it is not making a profit. Clients and shareholders are main stakeholders in running business. If companies betray their stakeholders, it means that they turn their back on profit providers. Thus, this requires them to do business at least in legal boundary. For one thing, there were some milk powder companies in China several years ago. They used illegal ingredients for making milk powder, because those ingredients are less expensive. 

For one thing, there were some milk powder companies in China several years ago who used illegal ingredients to make milk powder, because those ingredients were less expensive.