another the weight value gets lower that 50% until it gets to say 10% and as it gets closer to the other toe it increases until it gets to 50% at the center of that toe


Like this
---------------
shoe vertices      1      2      3       4       5         6         7        8       9    10       11     12
big toe                50   50     40     30     20      10
next toe                              10     20     30      40       50      40     30      20     10      
next toe                                                                               10     20      30     40      50
center                       toe                                           toe                                            toe              etc

center is showing where the center of each toe is. Also notice that the weight painting on all vertices add up to 50% and needs to be 50% because the weight painting for each of those vertices also have 50% on the foot


I don't normally do this with shoes, I normally just use the weight mapping that Blender does automatically without including the toes at all
I normally do this sort of thing with with meshes such as dresses so the vertices between the legs move better. I described how I do that here in the 9th post called weight painting the clothes
Maybe your circumstances might need something like this with shoes ?????

I do think this suggestion is going overboard for something like shoes
but I'm just adding this to give you some extra ideas. Whether you actually do it or not is something you will need to decide for yourself.