With more data, this does not look like a clever piece of airmanship and I can understand your frustration - although these people are also potential punters for your field, so there's perhaps a balance between frustration and income stream
You mention that the flight may have originated from abroad - does this imply foreign crew under the licence of another authority? (I am assuming not, but it is worth asking.)
PPR, to me, means exactly what it says. It may or may not require a prior telephone call. I can think of several airfields close to me where you can call up 10 mins out and they're very pleased to see you - Southend certainly used to, but I haven't flown in there for a couple of years, others such as Conington and Fenland were known to be friendly too.
Having said that, I'd usually telephone before the flight, if nothing else, just to check any differences since last time. I'd also check my Bottlang and if it said PPR by phone or telephone briefing required, then I would comply.
One of the airfields that I used to fly out of suffered constantly from aicraft landing without PPR, especially with the a/g station was unmanned. This was a noise sensitive area and sensitive to movement volumes, so they used to become frustrated too.
In fact I remember one berk taking off on the taxi (90 degrees across), whilst I was on very short final for the runway, turned out he was talking to another airfield completely!
So, there are examples of bad airmanship out there, but then again I could recall a number of issues I have had with controllers, including one where I was cleared to land with conflicting traffic, resulting in an Airprox and investigation.
Thus I suspect, that aviation is similar to America - you can look for whatever you wish to find and expect to find it with a high level of confidence
I'll leave Whirly and others, who see more pilots than me, to comment on the general standards.