All's well that ends well

I've only had to call an ambulance a few times, and for those events the ambulance was clearly needed. Tonight, though, it really wasn't.
Kevin and I got home from a nice evening stuffing our faces with sushi to find an unconscious man lying on the first floor landing in the converted terrace we live in. We recognised him as having something to do with the woman who lives on the first floor, but he was pretty unresponsive. I tried to wake him, but although he opened his eyes, he hardly moved at all.
What do you do when there's an unconscious man passed out on your landing? To be honest, I am not capable of just leaving someone lying there, even if I do think that there is nothing more wrong with them than drunkenness. You simply don't know what might actually be the problem and can't assume that nothing serious has happened. So it was time to call the ambulance service and try very hard to apologise whilst explaining that I didn't think it was a serious matter.
The ambulance was here in seconds. I mean, literally. I've never seen an ambulance turn up so fast. The crew were lovely, and I apologised to them again as I explained what had happened.
They managed, being big beefy men who are used to this sort of thing, to rouse him, find out that he was indeed just drunk and get him to admit that he didn't in fact live here.
Now, the curious thing was, and this worried Kev and I, that the door to the first floor flat was open when we came across him, but closed by the time we'd called the ambulance. Yet when we'd knocked, no one had answered.
When the ambulance men knocked, the woman who lives there answered, and assured them that he was drunk, and that he didn't live there, and they then persuaded him to leave.
All in all, an easy call for them, bordering on a waste of time. I apologised to the ambulance crew again before they left.
Thing is, what else can you do? He was breathing, yes, and appeared to be in no distress, but how can you just leave someone passed out on your landing and not do something about it? Because I read Tom's blog, I'm always really aware of the issue of wasting ambulance crew's time, and possibly stopping them responding to a serious emergency, but for incidents like this, I'm not sure what the alternative is. I certainly couldn't have just stepped over him and left him there.
As it is, he's left the building, but not the road, and has come back a couple of times to try to get let back in again. Hopefully, our neighbour will not acquiesce, and eventually he'll get bored and go home.