How is giving Goldman people government positions buying them if not by giving them the power to set rules as they like? It's not like they are in it for the cushy gov't benefits.
Just because you used to work for Goldman in the past, does not mean you are a current and future supporter of Goldman.
Nor does it mean that you are a bad person.
Trump is hiring people that know how these companies work from the inside-out. Which is the exact type of person you need to be able to deal with these companies head-on.
So it works. Integrity and patriotism matter of course. Diversifying investments prior to taking office would help reduce temptation.