Many shops have saamplers packs. But the problems I see are: 
  
that in many you can not choose your own selection of flavours. Or even a number of samples. 
  
They often sell samples in 10 or even 15ml bottles. 5 ml is ok. But still 5 times too much. If I don't like I throw away at least 4ml. What a waste 
  
They stock only their own brand. Some stock two or three. 
  
Is there a store that can offer me something like 10 brands of cherry, or virgina, or something like that? So I can compare. 
I'm form Europe, so ... maybe things are different here.