Store bought Mayonnaise is too vinegary?
You cannot. I hate vinegar too, and can assure you, there is no way to remove the taste. If dilution works for you, do it, it doesn't matter what you use. If you really can't stand the taste, dilution won't matter, then you have to throw out the bottle. 

"It doesn't matter what you use" means that there is no specific thing to mix in which will be better at "removing" the vinegar smell than some other thing. This is because you are not removing or changing anything about the smell, you are simply diluting - if you mix 50/50 with the filler, the mixture will only smell of vinegar half as strong. Which filler you use matters very much for the overall taste impression, it can happen that you dislike the new combination much more than you dislike pure vinegar. We can't tell you which combinations will make it better for you and which worse, it is a matter of personal taste.