Of course. It isn't a requirement and they would love help, as would the Night Shelter in winter.
Antifreeze is the section you want.
http://www.offthefence.org.uk/
I agree there are professional beggars which is different to homeless. I've seen professional beggars in court. I am not naive.
Calling everyone on the streets, scum, is not useful. It dehumanises them.
I will never give money to the homeless, but have given sleeping bags, hats, gloves...