Why does debstd strip non-debug libraries?

[hogendoorn r.a.]

While playing with flex 2.5.4, I discovered that libfl.a was stripped.
Consequently, linking fails because the symbol yywrap is not defined in
the library.

I got the source of flex and rebuild my own copy of the debian package.
It turned out that debstd strips all libraries, except the ones ending
on _g.a. Why?

Regards,

Rene' Hogendoorn