I often wander to the end of a platform, especially of a station that is new to me, just to see what's there both on the railway side and over the fence.
As for the Trespass and Welfare Officers, there was one at Surbiton the other day on the up island platform, 1 (on the slow line) and 2 (on the fast line). He repeatedly called to a dopey-looking young bloke to stay away from the edge of platform 2 as a fast was approaching. The bloke was standing right on the edge of the platform, and could have been in danger had he not eventually taken heed of the TWO's calls. I imagine that there are TWOs at Surbiton as there are a lot of services going through at a hefty lick on the up fast, the platforms can get crowded, and, because some trains on the up fast line do stop (most up stoppers are on platform 1), there are no fences along the platform as there are at Wimbledon and Earlsfield. There have also been several suicides at Surbiton as it's the nearest station to the local mental health facility that gives the opportunity for someone to jump under a fast train. I don't think I've seen TWOs at other stations on this line, except once at Earlsfield.