Looking at the maps it appears that the battles of Cowpens & Kings Mountain removed the small light force covering the inland flank of the main British column.  In each case the defeat of Ferguson & Tarleton opened the flank and rear of the British to to raids on the lines of communication.

This might be like asking why many Americans volunteered for Vietnam.  You won't get the same answer from every veteran.  I suspect if we could go back in time the same thing would hold true.

Generally speaking, a patriot is someone who loves and is loyal to their country.  But at the time of the American Revolution some Americans did not consider Great Britain to be their country or King George to be their King - even if all of Europe considered North America to be a British possession.  Then again, some did.  They were "loyalists," so to speak.  The two sides just had different ideas about people and place, kin and kind.

Taxation without representation was a big issue.  Some probably thought of it as a matter of principal.  Some were probably just pragmatic and thought it made economic sense.  I'm not saying one side was more "morally" right than the other.

Founding Fathers is a term used for the leadership of that era.  Here's a wikipedia definition:

Founding Fathers are persons instrumental in the establishment of an institution, usually a political institution, especially those connected to the origination of its ideals. The term is most often used in more reverential treatments of national history.

Sure, there's always a little bit of an extra reverential attitude associated with the idea.  As there is with many institutions.  The British regimental system sort of does the same thing in a military sense, doesn't it?