When using /clear in a command block, it ignores the team argument and clears the inventory of all players, regardless of team.

For example:
/clear @a[Team=Red] lapis_block

Acts like this:
/clear @a lapis_block

There's usually a delay between clearing Items, but it still clears the item.

Actually, if it's a block, it disappears from your inventory as soon as you try to place it, and it disappears as soon as it's placed.