Magic Band Usage Questions

Hello - this will be our first time using Magic Bands and a Dining Plan. My question is if I go up to a QS or Snack place and I want to use a credit for one thing, but pay OOP for another, is that going to annoy the cast member?
For sake of an example, if I’m at Kusafiri and I want to use a snack credit for a pastry but pay OOP for a coffee, is that okay? Can I still use the credit card associated with my magic band or should I carry a separate card for this purpose?

Thanks in advance!

You’re fine doing that. They’re used to it. A single band is all you need.

Thanks!