Your good reason has a corollary, which happens to be another good reason to use the original code. This modifies the original array:

@array = 1 .. 10;
for my $var (@array) {
    $var++;
    print "$var\n";
}
print "@array\n";
[download]

But this does not:

@array = 1 .. 10;
for (@array) {
    my $var = $_;
    $var++;
    print "$var\n";
}
print "@array\n";
[download]