Yes, it has to be disclosed by law. The problem was that the town I moved to, had large swathes of leasehold properties. It would have been difficult to find a freehold house. The council still owned the majority of the land.
The problem with leasehold is that ground rent can be raised. In my case, it was going up from £9 or £10 a year to over £100 a year. I think buying the freehold was something like a grand, or just over, so when I got the opportunity to buy, I bought it. Yes, the house was sold, so I 'lost'...
No, there are quite a few towns, where the council hold the leasehold of many houses. I lived in one for 9 years, with a very small ground rent of something like £9 a year. The council decided to sell the leases of the entire road to a London based company, but under some legislation or other...