Gift Certificates

Has anyone ever given gift certificates as a door prize, etc or donated one to a charity and NEVER heard from the bride?   This has happened to me on numerous occasions!  I have donated my services twice and never got a call.   I have given certificates as a door prize at a monthly local event and have never had a bride call.  Is this strange or do brides just collect this stuff and throw it away?   I would love to hear from you.