When I was in South Wales last autumn I did not walk from hostel to hostel, but just did day trip hiking on sections of the Coastal Path (I dislike carrying my stuff and also have never been camping). However I met a ton of people who walked the Wales coastal path and several who were camping when there weren't hostels, because they found Bed&Breakfasts too expensive. But Wales has been a popular tourist spot pretty much ever since modern tourism started, so tourist infrastructure of all kinds is very good.

Even without camping I only had to stay in a hotel once, because for some reason there wasn't any hostel in Swansea and the budget hotel was cheaper than most Bed&Breakfasts (I don't do Airbnb or such on principle because I think they worsen rental prices and find the whole principle anxiety inducing besides).

And while hostels aren't as cheap as they used to be (otoh not as bare bones either), that's definitely cheaper than hotels and often more fun too. (In case you haven't stayed in hostels often, at least in the ones I've stayed here in Europe you usually get a good mix of ages and demographics, though a few cater exclusively to young adults, but normally it's a mix from students to retirees.) Anyway, I can highly recommend that option for anyone who is not super fussy. (I mean, most hostels I've stayed have been clean, safe and fellow guests are usually considerate, but you do share facilities and have to deal with others, so it's not for people who get grossed out as soon as they see a stray hair in a sink and wake up at the slightest noise.)