Placing down redstone on side of a block with a repeater replaces it

Aiming in the side of a block, with an adjacent repeater, and placing down a redstone dust, will replace the repeater with redstone dust.

Also happens with comparators, torches, buttons, signs, saplings, grass, flowers, pressure plates, slabs, chests and many other non-full blocks in the game. In survival, this causes the loss of the block.