Those plug kits can certainly help with some classes of flats - like if you pick up a nail or something. For a really slow leak, I could use the pump to keep the pressure up and wait until I was at home to attempt this. I guess it would suck to have to try and use it in the winter, but it beats the alternative.
There are rare situations where the tire is so damaged that none of this helps. Certain types of road debris, or unusually large potholes (which can damage the rim). Then you are at the mercy of a tow truck showing up whenever they feel like it.
I guess I am cynical because years ago I had AAA, and I had a non-tire related issue one day. It was cool, but not cold. Nice sunny day, right in the city. Called AAA - took them 3 hours to show up. A police cruiser came by and they recommended that I call someone else, which was my first clue that they had a bad reputation. Apparently AAA doesn't pay the truck operators very much, so they tend to not place a high priority on calls that come in through AAA.
With the Kona, there is Hyundai roadside assistance that one can call. I haven't needed to call them, so I have no idea of how good the service actually is. They claim 24/7. Who knows.
If I had a spare, a tire issue would be a 10-minute nuisance. Apparently most people these days are incapable of changing their own tires - a general dumbing down of society, I guess. So they figure if most people call for roadside assistance, why bother supplying a spare. Now if you had a spare and called roadside assistance, they could change it for you. Without a spare, odds are you are looking at a tow (unless the towtruck operator uses a plug kit on the side of the road, but even then you have to wait for the guy to show up).