WordCloud: do not eliminate duplicates

Make it render the same but be a different thing:

RawBoxes @ TagBox[ToBoxes[#], Unique@#] & /@ {foo, foo, foo} // WordCloud

Or shorter but less documented:

DynamicName[#, Unique@#] & /@ {foo, foo, foo} // WordCloud

lst = {"foo","foo","foo"};

WordCloud  @ MapIndexed[Interpretation] @ lst

Also

WordCloud  @ MapIndexed[DynamicWrapper] @ lst

WordCloud @ Map[Labeled[#, Invisible @ Unique @ #]&] @ lst

WordCloud @ MapIndexed[StringJoin[#, ConstantArray["\[InvisibleSpace]", #2[[1]]]]&] @ lst