This is a hard topic.
In the first place i have the same feeling as Harry about the matter without the Bourbon is inferiour part

. Yet i find Nick's point more in common with my own opinion.
i totally disagree however with Peatreeks view (sorry about that).
In my opinion all whiskies are of the same quality generally speaking. I have the same affection and interest in blends, vatted, single malt- and grain, bourbon,Rye, irish whiskey etc. and would like to know all of them. However, even though they all inspire me that doesnt mean i find them all equally good in taste. Thats a matter of personal taste, and thats the solution to this topic i believe.
Americans are grown up with bourbon and rye, so it is only logical they have a natural favor for them. They grew in the distinctive flavor of those just like we belgians grow up with the different kinds of beer. However, here in europe (im gonna narrow it down to only Belgium cause then i know what im talking about) we learn to taste blends, then single malt, and only then is the step taken towards Bourbon and Rye.
The simple fact that we first grow in the malt flavors and learn to apreciate its complexity before we get confronted with the very sweetish corny flavors of bourbon is probably what causes many to put bourbon down. It tastes so very different then other whiskies that it needs time to develop. I must say, i try regularly a new bourbon but i still havent found my way in it. I keep sampling new ones because i realise its a flavor you must obtain (at least i hope so).
So i think its a matter of personal taste and the fact it tastes so different then other whiskies that makes it quite hard or unaccesseble for the common "european" whisky enthousiast to apreciate Bourbon.
Snobistic behaviour has nothing to do with it IMO.