That's because CVS is hosting Halloween Party.
According to the CVS Facebook page, children who go to CVS in costume on Sunday, Oct. 22, 2011, will receive "a free Halloween gift pack and complimentary photo with any purchase on October 23, 2011 at all CVS/pharmacy locations, while supplies last. The gift pack includes $5 value of candy, toys, trick or treat safety items and $10 in coupons for additional Halloween products! The gift pack also includes a free 5X7 photo, supported by an in-store costume photo shoot."
The times offer by location, so you'll want to check with your local store to see what time to go.