Yeah, it is normal... I get a lot of numbers when I work at the farmer's market from young military guys buying barely anything. But the older generation tends to tip even when they aren't suppose to... *has had an extra five bucks because she helped an older lady shop and load her cart on a slow day*
Nice, did you cover up the chest for the interview? You should get some good tips between your friendly attitude and looks. Don't be surprised if your best tippers are old men.