Well, the revolution was in the late 18th century, not mid 15th :)
And yes, that is the upper class I referred to who are still practising catholics.
The middle classes also retain a lot of these values and culture, without the strict religious practice in most cases.
It's not really such a small group - most of my friends and acquaintances (and pretty much everyone I've ever worked with) have belonged to one of these two groups, who represent a large chunk of the (urban) population here!
The working classes are not generally religious at all and mainly consist of blue-collar workers in cities and agricultural workers in more rural areas.
There is obviously a separate social group in the greater Monaco area I've never encountered, however, and I'm intrigued that their values are so different from similar socio-economic groups in the rest of the country!
Have you ever worked in France, btw? or do you just hang out at the beach all day drinking rosé?
I'm surprised you haven't come across the type of people I've been referring to, as they are pretty easily identifiable (and they tend to be found in managerial jobs in lots of firms). Like Hattie said, they are quite homogeneous and follow a fairly formal dress code etc.