Your going for a natural look but the thing is they dont live on walnut shells or sand. They live on hardened clay and dirt rocks grasses and branches. Not a few inches of sand. You said the pet store person told you it was fine.Well for future reference, not all pet store workers know what the heck they are talking about. I was told to feed my hatchling MEALWORMS. Hello recipe for death. They kept him on sand in the store. Told me to use a coil UVB which is hard on their eyes. I recommend Arcadia lights its what I use. He was also riddled with pinworms and coccidia and they said neither where any big deal but from what I understand coccidia will kill them and it was "no big deal''. I use tile for my beardies it keeps their nails trimmed and they can rub on it to remove shed.
You shouldn't want your cage to "not look ugly" the bearded dragon most likely wont know the difference or care. It's you who doesn't want unsightly paper towel. Your cage should be functional and safe! Lowes will cut tile to the size of you cage. Don't use anything with an adhesive on the bottom.
The walnut or sand or calcium sand can and will kill your beardie. If you want your beardie to stay alive and healthy get a proper substrate. When he eats his food if its going across the walnut he can get a whole mouth full of the walnut stuff and then bam you have a dying beardie who needs an expensive operation to save his/her life or you can watch them die slowly and very painfully.
People on here are trying to give you good advice, some people on here have had beardies for 20+ years. My herpetologist (someone who went to college for 6+ years coming out with a degree and knowing what reptiles need and they work with reptiles and knows more than a pet store worker) recommended using tile when I used reptile carpet. It's your choice to follow advice or not its your dragons life at risk. I hope I can speak for everyone here, we just want your beardie to be safe, happy and well cared for. Along with helping the handle understand the dangers of what their doing or praising them for their great husbandry. It just depends on the situation.
These are my cages.
I think they are very nice looking cages, they are functional, safe and they do look good but I did have paper towel in both of them even then they didnt look bad really at all.
This is when I first got the cage but the dragon was not in it yet. I just got the tiles yesterday and have had the cage for about a month.
Again no one is trying to be mean they are trying to help you and your beardie.