Threads here are allowed to develop and divert as normal conversations do. One idea sparking another. Personally I like it that way ~ as I like talking to people in a real pub.
I have to say, though, that in all the of pubs I frequented over the past 45 years I have never met anyone who, for no apparent reason, pulls out a picture of a girl with a large bust and shows it round.
If you want to simply post photographs there are threads for that in the Library.