Less Than Zero Seeds

I was looking for seedless oranges the other day. Here's how the conversation with the lady selling oranges went:

Me: zhè zhǒng yǒu méiyǒu zǐ? 这种有没有子?Does this kind have seeds?Lady: méiyǒu. 没有.NoMe: nà zhǒng ne? 那种呢?What about that kind?Lady: nà zhǒng gèng méiyǒu! 那种更没有!That kind has even less!

Can anyone explain this? I thought méiyǒu 没有 was none, nothing, zip. How can you have even MORE none (gèng méiyǒu 更没有)?It was actually a little test for her. Although I'd never shopped there before, I know what kinds of oranges do and don't have seeds. The first kind certainly DOES have seeds and the second kind DOESN'T.My only explanation for this is cultural, something I like to call: "Sell him what he wants even if you don't have it."I still remember when I asked a guy if he sold waterproof gloves (fángshuǐ shǒutào 防水手套) and he just pointed to a random pair of normal work gloves. I asked several times if he was SURE these are waterproof. He finally cracked and insisted that he could get some for me if I came back in a few hours. The shop was near my house so it was easy to check back. When I got back, he looked around nervously and then pointed to the same pair of work gloves again. He seemed to be afraid of saying he didn't have something I was looking for.That certainly doesn't happen all the time in China, but I think that might have been what was going on with orange lady. I asked a question about something she was selling. She thought I wanted to hear "no" so she said "no." Any other theories?