How are coins priced?

Just back from the UK, and I noticed most dealers tend to price UK coins highly, while letting 'foreign muck' slip through the grate at awesomely low prices (£20 for a 1 lira of 1915 in XF). I've always thought that dealers in their own countries would price their own coins less, (i.e. because they're less 'impressed' by them), while encountering foreign stuff wouldn't hesitate to slap a three digit tag on them. It seems to be like that in developed countries (the UK, France,etc), while less well off countries (Singapore, Japan, etc; prefer pricing other countries' coins more unfairly than they would their own)

Anyone have a similar experience; or any theories as to why this phenomenon might have come to be?

Hi Cass, I made a far lengthier reply than intended and as I don't want to detract from your interesting question I've posted it here instead. After the first two paragraphs you can safely skip the rest of it :)

A lot of it comes down to basic supply and demand.

Most collectors collect coins from their own country ( I know I do), therefore there are more collectors of UK coins in the UK than there are around the world.

All collectors want the best grade coin that they can afford. Because there will be lots of lower grade coins but a limited supply of top quality coins and more people vying for the higher grade coins, they will go for higher prices.

So in most countries you'll find that the lower to medium grade coins are as cheap as chips, whereas the higher grade coins will sell for good prices.

I would love to know your definition of developed country and well-off ones
That aside most often it's the case that you value what's from your culture more than what's foreign (yeah I know there are some strange people where this is not the case or even the opposite ), you will have a bigger supply but also a greater demand for the coins.
I don't know the pricing cultures of many countries but I think in most locations you will meet both extremes and those in between.
My personal experiences:
2nd and 3rd German Empire coins are relatively cheap in comparison but the scarcer and with better condition you will exceed catalog prices but that's often the case.
I get Japanese coins quite cheaply in Japan but sometimes I get them even cheaper from Europe or the USA. I don't see that many non Japanese coins there and many dealers slap quite a bit on the price tag (a bit more scarce unusual coins).
The Americans mostly care about their money and even they don't seem to like their own coins.
The foreign stuff most are indifferent about it at best so if you are lucky you can get very nice coins often for their material value.