Why not free downtown parking year 'round?

Presumably the City went to the great expense of installing parking meters throughout downtown for two reasons:

1) To ration scarce parking space, in some locations to half an hour, others an hour, and others two hours.

2) To raise revenue. (Just this year the City raised the cost from $0.25 for 15 minutes to $0.25 for 12 minutes to general annoyance.)

So why during the busiest time of the year, the Christmas shopping season, has the administration put hoods over the meters?

If it makes sense to provide free parking for two hours and forego the revenue in December, wouldn't two hours free parking make even more sense the rest of the year when merchants are eager to attract customers?

Limiting street parking to two hours effectively prevents all day parking. ('Meter Maids' mark a tire with chalk.) Free parking makes downtown competitive with the suburban shopping centers.

Let's keep the bags or get rid of the meters.