I would suggest that you respond to the request of a kick out clause (we call it a right of refusal here in Arkansas) with a suggestion that the clause be removed upon loan approval of the buyer. That way, everyone is satisfied. The seller will know that they do in fact have a solid buyer and the buyer will certainly be able to understand that with the amount of loans being denied in todays market that it is not unreasonable for a seller to be wary.
Sometimes we have to put ourselve in the sellers shoes.
Let me know if this helps.
SUGGESTION: Kick clause only in effect during option period.
If you do this be careful you are not an attorney, your broker might be able to help with wording.