Numbers and Not Labels?

I think it would be good if you could specify numbers instead of labels. It could remove the need for some labels and it would make something like this less complex:

Function .onInit

  MessageBox MB_YESNO "This will install. Continue?" IDYES 1

  Abort

FunctionEnd

...instead of:

Function .onInit

  MessageBox MB_YESNO "This will install. Continue?" IDYES NoAbort

  Abort

NoAbort:

FunctionEnd

The '1' would mean 'skip the next 1 instruction' and you could even perhaps use negative instructions to say 'go back 6 instructions'.

Wasn't there something like this in older versions on NSIS? If so, why was it removed?

It used to be numbers... then labels came, because it was easier. And for a short time, both where possible. But I don't recall the numbered jumps being removed... Anyway, you could jump back with those jumps, and counting instructions was hard.
Isn't it still in there?