These will ring up $5 in a transaction. Just doing a price inquiry in-store will still show $19.99. Have someone actually start the sale and it will ring up $5.
Also, these can returned within 30 days, regardless of price. The only problem might be if it's been opened since they can't confirm whether the subscription was started or not.
hiccups, I'm almost certain the activation does not have to be done in-store.
BTW, my store sold out of about 120 of these in less than 24 hours.