I think to understand more.
Of the 3 websites done for travellers hosting, couchsurfing.org is the most known and the most used, far from the others. This website has a large number of groups with a lot of actives ones. After subscribing to couchsurfing.org several years ago, I had the occasion to participate to parties organised by couchsurfers of around my place and even to participate to meetings, one in another region, the other in a neighbour country, after discovering these meetings from an annoncement on a group I built myself.
On bewelcome.org, the number of groups is really smaller (at least, it permits to see the complete list), but the most important for most of them, no message was steel written on them. Last febrary, a young guy of Quebec inaugurate the group "Last minute group in Paris". He was my first traveller, and later, I susbscribed to this group which has presently 2 members, the other, the man who created the group is living still fasther from Paris than me. To compare to the group "Paris EMERGENCY couch request" on couchsurfing.org, it has 6258 members. I am not there because I prefer preparing things in advance and I think to live too far from Paris for a really cheap way to reach me.
In fact, on bewelcome.org, there is nearly only the group of Toulouse (France) often putting messages about parties and other activitie between bewelcomers. For me who spend most of my holidays near this town, it may be an occasion to meet them but the bad thing is this cases if about the only exception.