Interesting questions. I think for everyone who does all or part of the Camino there's a different story, different motivation and different experience. I did it as part-tourism, part-pilgrimage. I'm not a Catholic, but there's no heavy Catholic ownership of the Camino until you arrive in Santiago. Along the way you'll meet people from all faiths and none, you'll stay in albergues (hostels) run by all kinds of individuals, organisations and fraternities. I stayed at a mainly Buddhist one and I dropped in and chatted with a bunch of people who maintain the traditions of the Knights Templar!
I'm in a pretty good place in life at the moment generally, I went for the pleasure of the walk through a part of the country I'd never visited before, for the peace and quiet of a couple of weeks away from daily life and I went in order to meet a bunch of interesting people. Mission accomplished on all three fronts!
I was advised to, and did go alone. Good advice, because unless you're a very solitary soul, which I'm not, you are forced to interact with complete strangers and that's been one of the beautiful aspects of the journey. I met people from Japan, South Korea, Tonga, Singapore, the US, Canada, Brazil, Italy, Germany, France, Austria, Australia, New Zealand and from every corner of Spain, of course. Funnily enough, in my 2 weeks on the road I didn't meet another Brit. I met people on genuine, religiously-inspired pilgrimage; youngsters on gap-years 'doing' the Camino; retirees getting away and seeing the world; professionals taking a break from stressful lives; and a few new-agey 'seekers' of some kind of kinetic truth as they walked the walk.
I found that I spent a lot of time walking alone, possibly a little over 50% of the route, and that was great, especially in the more beautiful regions of eastern Galicia where you just want to soak in the tranquility and splendour of the place. I found myself hooking up with others in the latter stages of a day's walk, as we approached my chosen stop-off. I'd often have late lunch or dinner with others and those are really lovely, sociable, communal experiences.
When you're on the Camino days start and end early. Most albergues insist you vacate before 9am (some before 8!) and they switch lights off in communal dormitories at 10pm, so I found I was walking before sunrise (c.8.30am); spending 5-6 hours on the road; eating, resting and then socialising in the afternoon; and then in bed by 9. That's the routine, and routine becomes really very fixed. I think most people find that. Despite all those clicks I covered, I've come home feeling really rested, fit and calm.
I can't recommend it highly enough as a stress-busting, meditative, sociable and personal break with the daily routine of normal life. I didn't 'find' myself, I didn't achieve salvation or enlightenment or any kind of state of grace, but I have had a great two weeks and come home feeling terrific.