If there are children involved then Social Services have to provide housing or they will be making children homeless. If a family is evicted for having parties / anti social behaviour / non-payment of rent this does not necessarily mean that they do not care for their children i.e. that they are not well clothed, well fed, loved and cared for - how could social services then justify breaking a family up by putting the children into care and turfing the parents out on the streets?
When you have to leave for your own safety a place can be found, because, presumably, your safety is paramount and the area in which you are housed in irrelevent. Authorities outside of the authority you belong do not have a duty to house you, in fact, in my experience, the most you can expect is travel expenses to get you back to your own authority area, who may not be able to house you. Otherwise you end up having problems that are experienced now when polices are changed for example in sheltered housing blocks where age limits were lowered from age 60 entry to age 45, in order that some homeless people could be housed, this unfortunately encouraged the newly housed persons to invite their street drinking friends to the property and cause problems for their elderly neighbours and wind up being evicted for causing anti social behaviour. Rough sleepers often suffer from mental health problems and so are unable to maintain a tenancy themselves even if they were offered a property, but appropriate housing is often not available, forcing them back out onto the streets again. It is a viscious circle, some people are not used to living in a property and having respnsibilities and so find it difficult to cope, sadly our support services are often inequipped to deal with these people and so the fall through the net and are only picked up when it is too late.