Why does setting the " LD_LIBRARY_PATH" also sets the environment variable on Linux?

[Yuri]

I am running this script on Linux and FreeBSD:

LD_LIBRARY_PATH="/x/bogus1:/x/bogus2"
LD_LIBRARY_PATH_ENV=$(env | grep ^LD_LIBRARY_PATH= | sed -e 
s/^LD_LIBRARY_PATH=//)
echo "LD_LIBRARY_PATH_ENV=$LD_LIBRARY_PATH_ENV"
On FreeBSD it prints "LD_LIBRARY_PATH_ENV=" as it should.
However, on Linux it prints "LD_LIBRARY_PATH_ENV=/x/bogus1:/x/bogus2"


Why does LD_LIBRARY_PATH="/x/bogus1:/x/bogus2" set the environment 
variable on Linux?

bash-5.3


Thanks,

Yuri