During a Tuesday visit to the American Museum of Natural History, Omaha resident Mary Stefano, 49, struggled to understand the concept of suggested donation. 'So, if the sign says $10 is the suggested donation, that means I have to pay $10, right?' Stefano asked the admission-counter cashier. 'Because, if you could pay less, why wouldn't everyone pay less?' After the cashier explained that $10 is what most adults pay, but museum visitors have the option of paying more or less depending on their ability, Stefano replied, 'But if I don't pay $10, I won't get to see the whole museum, right?' After another 10 minutes of queries, Stefano was escorted out of the museum by security. 