Arwen warmers are those big granny knickers that she had to wear when she moved back to the much more chilly climes of Rivendell from the balmy Lothlorien...
Lobelia is one of the middle classes so obviously Gollum's granny will be far more frightening. To illustrate my point, who would you rather take on? Anne Widdecombe or Ena Sharples? It would be a tough match but I suspect Ena would have more gumption in the end.
