There's a good number of punters who say "if no face picture, no punt". So that may have a bearing on why some WGs do show their faces.
As we know, a significant number, perhaps the majority do not. (My own experience is around 50/50 as on balance I'm keen to 'see before purchase').
Were I a woman, say single, in need of cash, with a bit of a libido, a fit body and so forth and confident enough about my surrounding neighbourhood and family to think that discovery would not risk things she values then a face photo might be on offer.
A single mum I've seen three times recently in Chester has a wad of face pictures on AW and gets good business. It's entirely possible that a neighbour will at some stage become aware of what is taking place but I think her attitude is that she is working to maintain a decent standard of life for herself and her juvenile children and is not causing clamour in the street nor indeed parking issues. So far push hasn't come to shove. But I'm sure this doughty woman will prevail over all issues.
Uncle Pokey