so i know that corn cob litter is a no no so i was at the pet store going to buy new bowls and some water bottles for the fids (found them cheaper on ebay) but i was up there playing with this bf female zon named lucy my ? is the pet store had corn cob litter in the bottom of the cage and the top where the play top is there was no crate or nothing to keep the bird from getting in the litter when i asked them they told me its okay to use??? whats the outlook on this??? i was at my vets today and forgot to ask!

heres a pic of the bottom of the cage with no crate.