Anyway loneliness is usually for 52 weeks a year for a lot of people, not for a week or two.
A family holiday can be great, I've done it, enjoyed it...aside from the fact that a DIL thought a holiday essential was staying up as late as possible each night, drinking. Knowing the 2 year old would be up early and raring to go...I digress
What about the families who cannot afford a holiday? What about the older person who cannot afford it either? And loneliness affects many younger people too, those who live alone, single, divorced, no family etc. and are restricted from doing the 'normal' social things for one reason or another...health, disability, financial.
I also accept that a drop in idea is open to all sorts of problems, could be abused, have financial issues and face apathy/personality clashes/cliques in time.