I would not dare to say that gravity did not exist, although I would really like to know what gravity is?
In an atom the individual electrons do not attract to each other because they are repulsed by each other, being likewise charges. Individual planets have both charge signs of negative and positive. One could assume that the individual electrons charge of one body are attracted to the opposite charge of another body and vice versus? The inverse square law playing a role in the magnitude of force as in Coulomb's laws on charge. One could also assume the opposite and the likewise charges of two different bodies cause there to be a radius between the two bodies, a repulsive force.
I am not saying this is any sort of fact or theory , it is just really asking why is gravity mechanism not thought of as charge when the affects of charge are pretty much the same as gravity. I.e Could my electrons in my body be attracted to the protons in the floor by charge polarities?
Added - It seems like my posting ability has been removed.
Mass is not an explanation, if we was to say that mass is the property of the object directly proportional to charge, I think we have an explanation of mass.