I bruise really easily too. Could be a number of things with me, I tend to have a low iron count and platelet count.
Never thought about the hypermobility thing, I'm hypermobile but never thought it would cause more bruising, more me just means bits of me can move more than they are supposed to though the arthritis has levelled though out a bit now haha!
I also blame my ability to trip over thin air :)
I went swimming once and decided to learn how to do some dives so was in and out of the pool a lot, pulling myself out at the side. Got home and I was absolutely black and blue all down my legs. It was just one of those things for me, especially as I liked the more extreme kind of activities, bruises were pretty much a way of life.
Mine take a long time to heal as well, same with wounds too.