What I expected to happen was the block I was attempting to break would have no breaking animation

What actually happened was the block I was attempting to break did have a block breaking animation

1. Be in gamemode 0
2. Left click a block with any item or an empty hand for a short enough time that the block doesn't break
3. Go into gamemode 2
4. Attempt to break the same block with the same item or any slot that is an empty hand. You will see that a block breaking animation is played on the block, but the block never breaks.

Note: This result was gotten on a singleplayer world put on to my LAN using the 'open to LAN' feature.