All highlighted examples show how Herbert Hoover (1874-1964) believed that once the federal government started to take directly participate in the economic system the inevitable outcome would be the loss of freedom.
In the first and second examples he is saying that once the government starts to take part, it goes all the way into the private lives of individuals which would be an attack against the basis of freedom.
Hoover thought like this because for him freedom only exists in the private life when it's kept away and separate from the government.
The third and fourth examples have the same meaning as the priors only now he is talking specifically about economics. He believed the problem of the Great Depression should be figured out by private businesses and the government should only cushion the situation.
b. there was an extensive network of roads
The supporters you're referring to were called patrons. Patrons were usually wealthy merchants or people who have made their fortune in other ways and wanted to either have a picture of themselves and their family, or generally had a desire to support painting, some even decided to order paintings for the church in order to get in good standing with the church officials.
