Negotiating with a non-profit

[Mark Dante]

There is a property in my hometown owned by a non-profit that has been for sale for several years.  I made an offer on the property and was awaiting a response.  The realtor calls me to tell me that...surprise...another offer was just made by another non-profit but at a much lower price.   Closing date is the same.  Neither offer has financing contingency.  The seller is mulling over whether to sell to a for-profit company (me) or a non-profit for half the price.    As a steward of other peoples donations, does a non-profit have any duty to accept the higher offer?   I'd offer more, but I don't think price is the motivating factor.  Any suggestions?!