I think there are two things to note here:
a) QlikView can store values as duals, i.e. a value consist of a numeric representation and a string representation, for example any Qlik dates are in fact numbers, but formatted to date representation like 'MM/DD/YYYY'.
It's important to note that any distinct number (field value) can only show a single format, the same field value can not have two distinct formats defined in the symbol table.
b) If Qlik encounters a text string, it often tries to automatically interpret it as number, and if it does so when loading in the data, it assigns the interpreted number as numeric representation of the field value and the original text value as text representation, but it can only do the assignment for the first appearance of the value, Qlik will override any occurence of the same number with different format with the first format loaded (or in other words: there is only one place for a single value in the symbol table, the text representation is determined by the first representation in load order).
I believe this already explains what you see, 2nd, 6th and 7th line are all interpreted as 1, with format 01
The automatic number interpretation kicks in for the result of your expression X&Y but not if you use Text(X&Y)