Why does pt-table-checksum gives exit status 0 if slave is unreachable?

Question

I'm using pt-table-checksum version 2.1.4 for checking my master-slave set up. In the case when I forget to set up the right privileges on the slave, it writes an error to stderr like this:

# pt-table-checksum -d employees
Cannot connect to h=node03.mydomain.local                                 <== error
            TS ERRORS  DIFFS     ROWS  CHUNKS SKIPPED    TIME TABLE
10-04T15:33:33      0      0        9       1       0   0.014 employees.departments
[...]

However, the exit status of it is 0.

# echo $?
0

The number differences it will find is always zero, as it has nothing to compare against. And yes, documentation says to exit with status 0 if no differences or errors have been reported. But this does not make sense in most cases.

Is there a way to make pt-table-checksum not failing silently and reporting this as a general failure? Should I file a bug or is this configurable?

^{It proves to be confusing to more users, for example in this question: "pt-table-checksum help required".}