It has to do with lugnut/stud side load. Close is not good enough. It will be a improper side load of the lug nut/stud.
Clamping force is what you are looking for. Studs do not have very much strength in a side load issue.
A good example is VW and BBS wheels. VW uses bolts rather then studs. If you order a set of BBS wheels they will come complete with a new set of bolts. Part of the reason is the cupped surface of the BBS wheel bolt is different then a standard steel/alloy VW wheel.
It may work for fine for years. Then you can also have a sudden failure. I bet 30% of the aftermarket wheels on the street right now have the wrong or improper lugs.