Thoughts re Megillat Rut/Book of Ruth

The most shocking verse in Megillah Rut is this one:

"So she stayed close to the maidservants of Boaz, and gleaned until the barley harvest and the wheat harvest were finished. Then she stayed at home with her mother-in-law." (Megillat Rut/Book of Ruth, chapter 2, verse 23)

 

Let me get this straight--Boaz knew that he was a "redeeming kinsman," but he let Ruth glean through the entire barley and wheat harvests and didn't make a move to give Ruth or Naomi any *long-term* help until he was "shot-gunned" into it? What's so heroic about letting two widows beg for food between harvests?

 

See this old post of mine: 

Thoughts re Megillat Rut/Book of Ruth, Shavuot 5774/2014 edition