Seaside children's railways

Does anyone remember the seaside railways for children of all ages in the 50's and 60's?  As I recall the majority of them were pulled by real if minuture steam locomotives. Certainly the one at Southsea sea fron was a real steam hauled one.

Today nearly all are sham trains hiding a car engine under a plastic or fibreglass moulding.

I wonder what happened to all the genuine ones and why they went away?  Too difficult to drive? Too expensive to run and maintain?  No real profit?

I love the smell of real steam!

TF