Should/Should not sperm banks have a limit on donors?

http://www.msnbc.msn.com/id/44399494/ns/health-childrens_health/

I personally feel there should be a limit to how many offspring that one donor's sperm can have.  As stated in the article, if the children find out they have 50+ half siblings, it will make them wonder if they have ever came in contact with them or even simply want to meet them.  This can be difficult news to find out because most people do not think they could have so many siblings that they know nothing about and have never met.  Putting a limit on the amount of kids will also reduce confusion and headache on the donor.  If the donor finds out they have 100 kids and those children show up one day wanting to know why he never contacted any of them, it may be a difficult situation for everyone to handle.  The best way to keep down confusion would be to limit the amount of offspring allowed per donor, no matter who they are.