This has probably happened to me 3-4 times total in the last month, most recently just now with a L13 Casino. I'll happen to be on when a building is close, click the "Accelerate Free" button in the 4m50s-4m55s time remaining range, and get charged 1 gold ball. Not a big deal, I'm usually rolling in them from tourneys and achievements anyway, but a nuisance all the same.
Likely answer is client side and server side being a little out of sync, I'm probably gonna start refreshing before accelerating from here on out.
Likely answer is client side and server side being a little out of sync, I'm probably gonna start refreshing before accelerating from here on out.