Question about a preposition.
Hello! I've come across a confusing sentence:

In other words, these were elite track and field competitors with some serious horsepower, not a few college kids sipping ON cheap beer and living off pizza.

Tell me please, why is there a preposition ON? Personally, I wouldn't use it in this sentence. Thanks:))))

Question

Question about a preposition.
Hello! I've come across a confusing sentence:

In other words, these were elite track and field competitors with some serious horsepower, not a few college kids sipping ON cheap beer and living off pizza.

Tell me please, why is there a preposition ON? Personally, I wouldn't use it in this sentence. Thanks:))))

Answer

Hello Bogdan 
The sentence is correct. It is a progressive action and joins the action of sipping with the beverage. For those that might not know, "to sip" means to take small drinks over a long period of time. 
I sipped ON my champagne. 
I took a sip OF my champagne. 
Best wishes
Carolina

Answer

Collocation dictionaries are special dictonaries that show which words collocate (are used together).

Good commerical dictionaries include the prepositions and example sentences.  The New Oxford American Dictionary gives "sip" and "sip at," but not "sip on." However, "sip on" sounds completely natural to me and I'm sure that it's in other dictionaries.

sip | sɪp |
verb (sips, sipping, sipped) [with object]
drink (something) by taking small mouthfuls: I sat sipping coffee | [no object] : she sipped at her tea.

noun
a small mouthful of liquid: she took a sip of the red wine.

Of course, there are regional differences.

Answer

The sentence is correct