My husband is used to having steaks flavored with just pepper and salt. The Filipina in me is not quite satisfied with just pepper and salt. So while I cook my husband's steak with just S&P, I cook mine and my sons' with spices or marinated, then let my husband taste them. So far his tastebuds have accepted and appreciated the new flavors, and actually have at times asked for the marinated/rubbed piece, but still goes back to that which he grew up with: steak seasoned with S&P.
Well, I still love trying new flavors, and would still want to expose my children to a wide variety of food. I often tell my sons that when they grow up, I would not want them to be fussy eaters, as that would give their future wives a hard time. So I continue exploring.
I suggest other moms have in their pantry some of these spices in small quantities (it's always best to use them freshly made spices, than having all of them in big quantities but which will count years before total consumption). I usually get my dried spices from "Spice of Life" outlet near me. They sell these spices on a per weight basis, and at a much cheaper price than those branded found in grocery stores (Hannaford in my area).
Here are some spice rubs for grilled steak (from Cook Illustrated Magazine):
Chile-Cumin Spice Rub
3 dried chipotle chiles, stemmed, seeded, and cut into rough pieces, then ground together with
2 dried ancho chiles, stemmed, seeded, and torn into rough pieces
1 tbsp ground cumin
1 tbsp table salt
2 tsp sugar
Click on this post's title to see a pinter-friendly list of these rubs and marinades which I compiled from 3 sources.