We get a mixed turnout for our ceilidhs - a few native Scots, but the majority are a mixture of Europeans who enjoy a dance! Scottish / gaelic culture is very popular in Europe, and I think people are intrigued by the kilts, poetry, etc.
There were two major 'Scottish Weekend' events in Belgium this summer, each one attended by thousands of mostly Belgians, with 'highland games', dancing, food & drink and lots of merchants - which were a mixture of Scots and Dutch. I bought myself a new kilt from the Dutch Kilt Store, for example, which sells lots of clothing, as well as organizing team building events on a Scottish theme.
There are several drum & pipe bands in Belgium (all native Belgians), and several Scottish / Irish dance troupes as well. My ceilidh band is 50% Scottish and 50% Belgian (if you count me, an Englishman, as Belgian, which I almost am).
The most surprising thing to me though is the Freemasons - for the last 9 years the Belgian Freemasons have organized a Burns Night supper. I played at the last one with my band - 400 Belgians dressed in kilts / plaid / etc. and smashed on whisky (it was sponsored in part by Glenmorangie). They had sword dancing, a (Belgian) drum & pipe band, and us playing Scottish music, along with a haggis, neeps & tatties meal. The head mason was dressed as a clan chieftain and did an address to the haggis in English with a strong French accent. All very enthusiastic. Next year will be the 10th anniversary and we're invited back again for an even bigger event!
I don't think anyone here would celebrate St Andrews unless some native Scots arranged it. There are enough expats that there are usually several Burns Night events organized. And we just play our normal repertoire for St Andrew - the regular dances. For Burns Night it's usually more songs than dances.