it wont fill up your inventory if you have your hotbar full and its not on inventory screen in creative....
Picture it like this: You break a block and You might not have noticed that it had redstone on it(like it was above you, etc)... Then you walk away and try it and it doesn't work, and you then have search the entire place for the problem, which was the block you accidentally broke in the first place.
That's not a bug... That's normal Minecraft.... Break the redstone first then the block, it would break many of my creations if they tried to get rid of that (When i break a block the item on it falls onto pressure plates and ativates something and yes i am talking about creative mode not survival)... I'm not going to say "if they tried to FIX that" because its NOT a bug it is NORMAL
Just type /gamerule DoTilesDrop false.... You dont need to ruin many things for other people...