spring for vs treat

spring for

verb
  • To pay for; to offer money. 

treat

verb
  • To negotiate, discuss terms, bargain (for or with). 

  • To care for medicinally or surgically; to apply medical care to. 

  • To discourse on; to represent or deal with in a particular way, in writing or speaking. 

  • To provide something special and pleasant. 

  • To entertain with food or drink, especially at one's own expense; to show hospitality to; to pay for as celebration or reward. 

  • To commit the offence of providing food, drink, entertainment or provision to corruptly influence a voter. 

  • To handle, deal with or behave towards in a specific way. 

  • To discourse; to handle a subject in writing or speaking; to conduct a discussion. 

  • To subject to a chemical or other action; to act upon with a specific scientific result in mind. 

noun
  • An unexpected gift, event etc., which provides great pleasure. 

  • A snack food item designed to be given to pets. 

  • An entertainment, outing, food, drink, or other indulgence provided by someone for the enjoyment of others. 

How often have the words spring for and treat occurred in a corpus of books? (source: Google Ngram Viewer )