It's definitely not a scam, there's a lot of good free TV to be had with a C band dish. I have a few c band and ku dishes here and receive a ton of good channels.
I agree with Primestar31, set the lnbf Lo to 5150 instead of standard. Are you positive that you're connected to the C side of the lnbf and not the Ku?
What type of TV shows does your wife like to watch? With your setup, you should receive NBC, ABC, PBS, ION, MeTV, Movies!, CTV, CCTV, BYUTV, Laff, Cozi, DW, H and I, Decades, This TV, Fox, Light TV, Bounce, Grit, Escape, Retro TV, Buzzr and more. Maybe if she knows you can get something she'll like, she'll be a bit easier on you about it?