For the record, my two children both started life as frozen embryos.
We also had left over embryos which we donated to another infertile couple which recently resulted in the birth of a healthy, beautiful baby. I can assure you it was not an easy choice nor one which we took lightly. But it was the best for us.
Here is what President Bush has to say about Stem Cell research:
President Bush's Position on Stem Cell Research
To answer the OP's question, one of your basic assumptions is at least partially incorrect.
Embryos must be
donated by their genetic parents in order to be used for stem cell research; they're not just taken or given away by clinic staff. It's a legal process. Many people either don't know this is an option or choose not to go that route with their embryos. Many embryos languish in clinic's freezers because parents aren't sure
what to do with them. Most people I talk with say they don't think they could give their embryos to anyone else.