Raiding is a largely social and partly competitive activity to get people together to sail in areas they are not familiar with. So if you are very familiar with sailing in Carrick Roads and the Helford River, you are unlikely to be interested in raiding there. But if you have never sailed in, say, the Baltic, you might want to join the Finnish Raid, where you will get local support, some competition if you want it, accommodation, rescue boats, launching, mooring and trailer storage all sorted out for you, plus all meals, friendly evenings and a chance to see (and have a sail in) some really remarkable boats.
The first raid I went on was in the Solent, where I went with my brand new Baycruiser. I had a far better time and learnt far more by going in a crowd of mad small boat sailors from all over Europe than if I had just gone on my own and wondered what to do and where to go.
So most of those Raiding at Falmouth in September are unlikely to be regular sailors there. That's why I am going. I wouldn't want to join a Raid in Poole harbour, because I sail there all the time. But I would love to join the Raid in the Venetian lagoon. Sailing down the Grand Canal in a crowd of small, mad boats would be wonderful.