NEW YORK–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.