Unless they just don't talk about their kids ever, neither Wil nor Penny require a babysitter. Most single parents that I know go about 3 minutes in most social settings before mentioning their children.
Chez Albert's is apparently a real place.
Here's a menuIt looks like dinner would top out at about $50 a plate before wine (but including an Aperitif for each), so there's $100. Add a bottle of wine and we're at at $130 easy, and $150 if he's going for a nice bottle (I'm assuming based on usual wine prices, as their wine list isn't provided). Add 5% sales tax and we're at $157.50. Add 20% tip ($31.50) and we're at $189. That leaves $11 of flex room, and I don't see a desert menu there.
Now, chances are that Penny is a cheaper date then that. She's pretty thin and health concerned, so she probably won't order both a bisque and a side salad. She may prefer to share a light hors douvre. And probably doesn't drink much (I think she's said as much before), so may prefer that she just get 1 glass of wine instead of sharing a bottle and having an Aperitif. Also, given her perspective on dating, I see a pretty high chance that she insists on going dutch. But Wil doesn't necessarily know any of this and can't take any chances.
Edit: typo stuff. Also, man that menu makes me hungry.