I don't think they all have to have taproots, although many do. Others may depend on an extensive root system that can accumulate more nutrients than others. The root system of the woodland strawberry forms a symbiotic relationship with endomycorrhizal bacteria, and that may have something to do with it, too. I'm not educated enough about it to know for certain.
I think that deep rooting is a common feature of most dynamic accumulators, however this isn't always the case. Commonly, the plants are drawing minerals from the subsoil and concentrating them in their bodies. It is possible that plants are drawing in the nutrients they concentrate from the surface as well.
the wild strawberries naturalize all over my property..and we LOVE them..I have grown purchased strawberry plants and they dont do as well as the wild ones..ron loves to bring me a handful of wild strawberries..when he goes out weeding..they basically make a natural ground cover in my rear..mostly the prefer to pop up in some shade..here..i allow them to grow whereever they pop up
Bloom where you are planted.