Towels, bedding and such are for sale here on the island and it's not necessary to smuggle them in. If you do decide to bring them in a suit case the customs inspector will charge you a fee or several fees making it even more impractical. I've brought things into Belize in my suitcase by unwrapping them and not declaring but items that one might have in a suitcase normally like clothing and cameras. You might have some embarrassing and difficult explanations and find the smuggling business isn't your forte with no real profit to show for the experience.

White Sands Dive Shops Daily Blog