Packages don't actually use strict. strict simply takes effect until the end of the lexical scope in which it occurs (either file or block). Package declarations don't matter to the strict pragma.

Here's an example:

#!perl

use strict;

package First;

$x = 1;

package Second;

$y = 2;

__END__
Global symbol "$x" requires explicit package name at - line 7.
Global symbol "$y" requires explicit package name at - line 11.
Execution of - aborted due to compilation errors.
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