R/t shocking. Controllers talking to a pilot about buying his Warrior from him. General conversation over frequency. In this country you wouldn't get that. On the other hand I have heard some awful r/t here but not from the controllers.
There is nothing bad in having other conversations over ATC frequencies. It is actually fun, such as this one below.
Controlled airspace wise, the airspace is simpler. On my qxc I flew 200 miles without the need to enter any controlled airspace (apart from KFPR) or watch my height because of airways or CTA/CTR limits. I now fly around The Solent and that's way more complicated.
It is advisable to always talk to ATC when at the controls of an aircraft. Remember, it is all about safety, and communication is a vital aspect of ensuring aviation safety.
WP