When we first starting having playdates, we would work them around our LO's nap schedules. We'd play until the kids got tired, then we'd race home to put them to bed!
Now that the kids don't nap at all, Bee and I will often get together with parents of kids a similar age for dinner + a playdate, all in one. All the kids will play together, while the parents chat, eat and drink wine.
It used to be tough to balance parenting and hanging out, but now that the kids are 5 and almost 7, they are happy to just spend time with kids their own age! It's so great, and we're really enjoying spending time talking to adults. Ahh... it's been too long!
Do your LO's playdates ever extend over into dinnertime?