of course they can...
be it drug-addicts as well...
bhai gurdas ji says..."charan saran gur EK painda jaae chal, satgur KOT painda aage hoye let hai."
if these kinda ppl take their first step towards guru saheb...who knows what happens to them when guru saheb takes crores of steps towards them?
now if you say that you were jus talking about the city in itself and not sri harmadir saheb....then you shouldn't have written holy city either.