You quoted how it didn't spoil NHL so I had a look
from wiki
Each National Hockey League regulation game is an ice hockey game played between two teams and is 60 minutes long. The game is composed of three 20-minute periods with an intermission of either 15½ or 17 minutes (if nationally televised) between periods.[54] Television timeouts are taken at the first stoppage of play after 6, 10, and 14 minutes of elapsed time unless there is a power play or the first stoppage is the result of a goal. TV timeouts are two minutes long, and occur three times per period
So you have 20 minute plays with 3 stops of 2 minutes I'm not surprised you don't find the TV checking affects the flow of the game.
Football is 45 minutes each way no stops for anything. Two words: commercial sponsors
Also not related to this discussion.