grep behaviour is different when run using bash -c '...'

I met an interesting issue while working with this code from Stack Overflow: tripleee's answer on "How to check if a file contains only zeros in a Linux shell?" Why does the same bash code produce different result depending on interactive shell or subshell? Make all-zeros file with name your_file.

$ truncate -s 1K your_file

Interactive shell example

$ tr -d '\0' 

The same code but using subshell

$ bash -c 'tr -d '\0' 

And also interesting fact. I changed original example by adding -a option ("equivalent to --binary-files=text") because without this option interactive shell works but subshell:

$ bash -c 'tr -d '\0' 

P.S. I use bash 5.2.37(1)-release from Ubuntu 25.04