Trying New Things - Breakfast Edition

The other day I was grocery shopping with my littlest one and I remembered that we were running out of the cereal that she seemed to like that week.  She's very particular about what she eats -- I hate to say that she is picky, because she eats a lot of different things, but she's very particular about what she wants for breakfast and lunch each day.  Some days she's all about pancakes, some days she wants a "big breakfix" as she calls it, with Daddy's omelets and sausage or bacon.  Sometimes she's in the mood for cinnamon rolls, sometimes she wants a peanut butter and banana sandwich, and sometimes she's on a kick with a specific cereal.  Even her cereal preferences vary greatly!  She likes everything from Lucky Charms to plain Cheerios (no sugar added -- I always needed sugar on those when I was a kid!) to Raisin Bran without the raisins!  I can't remember the cereal she was on last week, but I know we were running low so I asked if she wanted another box.  She said, "Let me see what they have" and began to browse through the cereal aisle.  She came back with Cinnamon Toast Crunch -- her older sister is a big cinnamon fan, but she herself does not usually gravitate toward cinnamon flavored things...  I said, "Really?  Are you sure?"  Yep, I'm sure.  "Have you TRIED it before?"  Oh yeah!  "And you liked it?"  Oh yeah!  "Ok, toss it in the cart."

This is always a struggle of mine -- when I think I know what my child likes and dislikes and they are insistent that I do not...  I hate to waste money on things they are not going to like -- I can't tell you how many times my poor husband has been stuck eating some bizarre "children's" yogurt that our youngest has insisted she will love!  She's famous for trying something and telling us that she likes it, but she's going to "save it for later."  That means she's never touching it again!  But I also hate to discourage my kids from trying new foods -- I've even used the argument, when trying to introduce something new that they are certain they will not like, "You should try it!  It could end up being your favorite thing and you don't know it yet!"  (Tried that with my eldest and oranges -- yep, not her favorite thing!) 

Anyway, I gave in and bought the Cinnamon Toast Crunch and the next morning I serve it to my girlie who, as I might have guessed, picked at it and didn't eat much.  The day after that, I asked what she wanted for breakfast and she asked for the cereal that she had been eating the week before (you know, the kind I tried to talk her into in the store's cereal aisle...).  I resigned myself to the fact that I was now eating the Cinnamon Toast Crunch for breakfast and poured myself a bowl.  As I sat with her eating the cereal, I discovered that it gets soggy really quickly -- I was not a fan!  I said this to her and she said, "I KNOW!"  And I said, "So WHY did you want to buy this cereal?"  And she said, "I have NO idea!"  Sigh...

What do you do in situations like this?  Do you give in against your better judgment and hope for the best, or do you hold your ground?