Used correctly, a dry lube should be applied somewhat regularly, especially if you're riding in wet conditions (like, every 30-50 miles). You may find yourself going through what dry lube you have fairly quickly, and you'll likely be in a position to need to buy more lube soon anyway.
That said, bikes existed for decades with only the occasional shot of WD-40 (which has both solvent and lubricant), so keep that perspective as well.