We don’t really have heater vents around here. But there are doorways and other places that provide shelter from the rain and wind that are highly coveted. There are never enough shelter beds available – the Fire Marshall limits the occupancy and shelters could be fined if they exceed the numbers.
Some homeless people (especially Trans folk, but also other LGBTQ+s) fear the violence of some shelters and prefer to deal with the weather instead. Others stay outside because they have pets that aren’t allowed inside shelters. Still others don’t want to be separated from their human companions due to gender segregation in most shelters.
In Berkeley, they have a storm shelter that only operates when it’s rainy or very cold. You are protected from the elements, but it’s crowded and noisy. And only available when weather conditions are severe.
The shelter I stayed at in Berkeley is in the basement of an old brick building. Every evening, we walked past a sign on the building warning that it wasn’t structurally reinforced to withstand an earthquake. There was a minor earthquake centered in Berkeley while I was in the building for the night (but there was no damage).
Berkeley provides many services either through the city itself, or through churches and other organizations. Many churches provide one meal a month, but it’s coordinated so you can eat every day, somewhere. And there are groups that take food out to where the homeless congregate, such as People’s Park. UC Berkeley students put on a free clinic once a week in the evening when school is in session that provides food, OTC meds, massages, haircuts, eye care vouchers, and medical checkups.
Possibly a bigger problem than shelter is the lack of beds in recovery facilities. Even if you want to kick your habit, there probably won’t be a space available for you unless you have the money to pay for it (eg Betty Ford Center). The lack of sufficient services means that many people who could be living productive lives have not survived.
There are studies that prove that it’s much easier to quit your chemical addictions if you are housed, but nearly all programs require that you be clean before they accept you into their housing program.