On the sunnyside of the street

Once upon a time, streets in France were concave letting used water run down to the bottom, make that the middle. Citizens of high social ranking walked alongside the houses that is, at the top of the street, to avoid soiling their clothing. Could it be possible that some collective memory rests in the French of today, making them against all odds walk on their left instead of staying right as people in countries where one drives on the right normally do? Well, strangers to this phenomenon should know that this habit or lack thereof might hark back to another inherited memory and remember that during the French revolution, high society was brought low, chopped off and done away with and each member of whatever social standing could now take the high road. If this is the case, then what is the excuse of those other people who walk willy-nilly in the middle, on the right or on the left of the street with no rule in mind?