Minecart with Command Block changing its name

An unnamed Minecart with Command Block changes its name when reloading the world.

Reproduce:

1. Take an unnamed Minecart with Command Block "/give @p minecraft:command_block_minecart"

2. Build a track like the one on my screenshots

3. Enter the command "/say test" into the minecart

4. Let it go

5. The message in the chat will be "[Minecart with Command Block] test"

6. Leave the world and re-enter

7. The message in the chat will be "[@] test"

A Repeating Command Block with the command "/say @e[distance=..2]" placed on top of the Redstone Block confirms that. The name will change in that message as well.

When breaking the Minecart with Command Block in Creative mode after re-entering the world it wil drop a Minecart named "@"