Try it with warnings next time ;-)

with %$anonhash, {
   name    => 'dave',
   city    => 'San Francisco',
   phone   => '555-1212',
   hobbies => [ qw( Perl Anime ) ], # make the value into a scalar.
};
[download]

I'd also make the minor change:

sub with(\%$) {
   my ($hash, $values) = @_;
   @$hash{keys %$values} = values %$values;
}
[download]

Just a bit more idiomatic, IMO.