Generally speaking, I think the answer is no. As my answer will explain, the acts of sale and delivery require a licence, but Prohibition prevents licences from working in the "holdouts."
Liquor in Alberta is governed by the Gaming, Liquor and Cannabis Act (GLCA), whose liquor part starts with this general statement in § 50:
No person may, except in accordance with this Act or in accordance with a liquor licence, manufacture, import, purchase, sell, transport, give, possess, store, use or consume liquor.
That means in order to sell and deliver (transport) alcohol to the Prohibition area, we need either a licence or some other exception in the GLCA.
Let's try to obtain a licence, specifically a class D delivery service licence as defined in § 47(f) of the associated regulations. This would allow us:
(i) to take orders from an adult who wishes to purchase liquor,
(ii) to purchase liquor to fill the order from a retail or general merchandise liquor store licensee or a general or manufacturer’s off sales licensee,
(iii) to deliver the liquor to the adult who ordered it at a place where it is lawful to store or consume the liquor, and
(iv) to sell the liquor to the adult who ordered it;
Unfortunately we run into the immediate problem that Prohibition in Alberta is specifically a prohibition on liquor licences, according to § 541 question:
Despite anything in this Act, no liquor licence, other than a special event licence or a duty free store licence, may be issued for the area described in section 146(a) and (b) of the Liquor Control Act, RSA 1980 cL‑17, as it read on July 14, 1996.
Note that it's for the area, not just in. Additionally there's the language of "Despite anything in this Act" which clearly sets Prohibition in the area2 as a strong default.
So now we're stuck looking for an exception in the GLCA. These exceptions would be located within the portion under the header "Activities involving Liquor," §§ 76‑90.
While there is some room for interpretation, I would argue that there's no such exception. First, let me quote your scenario:
If a delivery service were to warehouse their inventory outside of the prohibited area, and transact over the phone using credit cards, could they still deliver liquor to customers inside the prohibited area?
There's three things here that § 50 prohibits by default: storage, sale,
Storage is easy to deal with. Since that's occurring completely outside the Prohibition area, we can just get a licence3.
Selling is murkier. However, I doubt a licence is valid in this case, because a licence doesn't cover activities for the Prohibition area. Note that the GLCA definitions sections includes in sale "the storage, display, advertising and offering of liquor or cannabis for the purpose of sale." It's hard to argue, especially when combined with the transportation, that you're not offering to sell to the Prohibition area. With a licence not possible, we would need an exception in the GLCA, of which I can find none.
Transportation does have quite the broad exception in § 83:
A common carrier or other person may, in accordance with this Act, transport liquor from a place where liquor is lawfully located to another place where liquor may be lawfully located.
- I'm not really sure how to interpret this with the rest of the act4. The "other person" portion at first appears to create a large exception. However, a broad interpretation would render many parts of the GLCA ineffective, and make the delivery service licence redundant. When judges interpret law, they generally do so in a way that does not render things redundant. Given the context, I would thus interpret "common carrier" an example of the type of persons to be considered in "other persons," because otherwise, why not use the phrase "every person." Given this, setting up a liquor delivery business would normally need a licence and not qualify under this exception, though I reiterate I'm not very certain about this one.
- CanLII has no cases citing this section, leaving us to do our own interpretation.
- The Liquor Control Act doesn't appear to be available anywhere online, so I can't confirm exactly where prohibition is in effect. Wikipedia says its Cardston County and County of Warner No. 5, two adjacent counties on the U.S. border, but it's not in the citation given.
- But, not the delivery service licence I mentioned earlier, since they specifically exclude storage (§ 54 of the associated regulations). We'll just upgrade to the retail store licence described in in § 47(a) which is a superset of the delivery service licence without the storage restriction.
- Again, we're left to our own interpretations here. CanLII only has one case referencing this section, and it's not really relevant. The person charged was sitting in a stationary vehicle with alcohol. Charges were dismissed.