Apple have engineered in the need for multiple iPads
By not allowing multiple user profiles in even the simplest form, Apple have purposely (cynically) engineered-in the need for multiple iPads rather than sharing. Anyone who has basic access to the iPad has access to any email accounts etc set up on it. It's not even possible to give a guest casual access without your email etc being accessed. Given that it was sometimes advertised as the ideal casual "pick it up and use" device this is woeful and is the reason I cannot recommend the iPad to anyone who asks me.