Those playset accessory variations definitely happened here too with the Dance School (and we also had legwarmers and shoes with some Dance Schools, which thanks to Babydoll was confirmed as not being a hallucinated memory a few months ago xD). There are tons of detail mysteries that can only be settled by people who've grown up with the stuff.
The 4 out of 6 is a feature of our line, too. Depending on the set, of course, it might be you had our distribution for some and US for other sets that were out worldwide. We had Candy Canes from both US and here, the US boxed ones as a store exclusive that included the two ponies not officially available in the UK. That may be a possibility for you guys too - that something was a store exclusive imported from elsewhere. In the UK the main culprit for this was Woolworths, but even now Smyths and Entertainer still do it with end of line stock from all over the place. I'm sure that muddies the line beautifully here - and I suspect it's probably true down under, as well, since anything in English language would be fair game to sell over there just as it was over here.