Thanks for the input girls.
Looks like the biggest reason for walking like this is insecurity and not wanting to draw attention to you and be approached by guys on the street. Those of you that say it's also because of the cold and to stop the bounce, I think those are just excuses you give to yourself to justify the behaviour, because you walk like that all year long no matter how hot or cold it is, and many girls with small firm breasts also walk like this (even thought that's not the case for most of you in this thread). Subconsciously the real reason may be down to insecurity but you're just not aware of it, not like phogirl69 anyway (nice post btw).
I was thinking about this earlier today, and I think the equivalent of this behavior for guys is walking with their hands in their pockets. Must be down to insecurities too, something along the lines of wanting to make their 'package' less noticeable.
