Has UA changed its beverage policy?

I always liked the fact that UA would leave the whole soft drink can in coach. Although they didn't do this on TED, they FAs on both United and TED always came back around doing refills.

Twice on TED and three times on UA this past month, all in coach, things were different. No cans given and no refills offered. Once, on UA, I initially got a 2/3rds full little cup of Diet Pepsi and asked for a refill when the FA was next down the aisle about 10-15 minuters later. I was nastily told "We're doing coffee now!" My seatmate said "WOW! - You might as well have asked to visit the cockpit!" We were 45-60 minutes into a 2+ hour flight.

These were all 2 to 2-1/2 hour flights with no tubulence or other oddities. Today, the FAs stayed in front drinking cola (with refills) themselves and buttoned up the galley about 45 minutes before landing. No one was ever offered a refill.

Is UA now trying to save money by having no soft drink refills in coach? Or have I had 5 consecutive examples of lousy service?

Does anybody know what Frontier's policy is? I have considered checking them out, as they are getting a pretty good route structure out of Denver.