OT, am I being stupid?

I have a mom's night out tonight at a restaurant at 7. These things usually go from about 7 til 9:30, so I'd be home around 9:45. DH was originally going to come home from work and take care of the kids, feed them dinner and put them to bed at 8:30. He found out there's a concert he's been wanting to go to and it's tonight, and he can get tickets. I told him I'd rather stay home than leave the kids with his parents, because whenever they stay with his parents, I get home and find the kids unfed (or eating junk food), watching TV (even though they know about my strict TV limits...they say shows like CSI and Law & Order don't count because they're not interesting to kids, but hello, they show corpses), and they usually have their diapers hanging around their ankles because they haven't been changed since before I left. Plus MIL is the biggest pushover when it comes to her grandkids, and all they have to do is bat their eyes and she'll start forking over chocolate milk, cookies, ice cream, candy, whatever. Once I went out and they were supposed to eat dinner here, and when I came back they had eaten almost an entire loaf of bread on their own but hadn't been offered ANY real food.

Now that I've vented on and on (oops) I wonder, am I being stupid/selfish/whatever to not want to leave my kids with them? DH says it won't be that big of a deal if they don't get to bed on time (to me it is especially because DS has night terrors if there's a shift in his schedule). He also said they might fall asleep on their own even if MIL doesn't do the night-time routine, and if that does happen, I'll have to come back home and wake them up so I can change their diapers to prevent them from leaking. I told DH he could go to the concert, but I was not going to leave the kids with his parents. I told him that from the start...then he called his parents anyway and set them up to babysit tonight, and is wondering why I'm not thanking him for finding a way for both of us to go out.