The /loot command does not spawn loot exactly where the location specifies.

This makes it impossible to spawn loot in the center of a block.

In the examples, the cords of the gold pressure plate are 3 100 3, and the world origin (0,0) is to the bottom right corner.

When I run the command /loot spawn 3 100 3 loot "entities/warden"
As expected the item generates at the origin of the block.

But when I run the command /loot spawn 3.5 100 3.5 loot "entities/warden"
The item continues to spawn in the corner of the block.

This happens with any loot table and any value entered as a decimal.