Learn English – Meaning of Top Gun quote

It appears to mean the following

... an amount to be used

• for advertising agricultural or industrial advantages of the state or county or any part of the state, or

• for collecting, preparing or maintaining an exhibition of the products and industries of the county at any domestic or foreign exposition, for the purpose of

   a) encouraging immigration and increasing the trade in the products of Michigan, or
   b) advertising the state and any portion thereof for tourists and resorters.
  

While the interpretation of complex and ambiguous laws keeps numerous lawyers busy and well paid, Courts tend to look to see if there is parallel construction to interpret what the legislature intended.

In this case, the start of the first main category is designated by for and the next is set off by , or for. The for in the purpose of phrase is not part of that series of main categories. If it were part of a series, either the second category would not have had an or and the purpose of clause would have begun with one, or all the phrases in the series would have begun with or.

SUPPLEMENT

It has been suggested that the portion I have listed as subparagraph b) should be its own bullet as a main category. [See @Dan's comment below for the rationale.]

There is some common sense logic to that, but I don't think so for two reasons. To be parallel, it would need or for, which it lacks. Also just to advertise the state ... for tourists ... seems broader than the product focused criteria of the other two main categories. (And now we are into legislative interpretation for which we need to charge lawyers' salaries.)

You would quote the original with an "as cited by" mention. For example

Writing in his The Perennial Pilosophy, Huxley quotes Eckhart: "He who suffers for love does not suffer, for all suffering is forgot."*

*[Eckhart citation here]