My wife's aunt, who with her husband ran a B&B in NC for years, described the problem as "velvet handcuffs."
Of course, that was before the Internet and cell phones and call-forwarding, and so they were prisoners of their phone, as well.
We're much more strict about early check-in than late. People who show up at noon with hope in their eyes and an explanation, "we just wanted to make sure we could find your place in daylight" can come back at four with the rest of the hoi polloi.
Occasionally, a family will show up in the early afternoon with shrieking children and desperation in their eyes and we'll take pity, because their room is ready. But I had to caution one dad about not trying to drown his son, a whirling dervish he had tucked under his arm, in the pool. "Our insurance rates would go up."
"You think I'd do that?!" he asked me, sticking his jaw out.
I looked at him and at the child kicking deep indentation bruises into his butt. "Well, I would."
We reached an understanding. They gave us an awesome TA review and turned out to be exceptional parents with very nice children, when there weren't blood-sugar and sleep issues.
Since we're here on-site, late check-ins aren't nearly the issue for us as they are from some other posters. In the winter, it isn't unusual for us to leave the lights on until the wee hours of the morning, in hopes that the Colorado Department of Transportation will have cleared the avalanche(s) on the pass and opened the road.
Truly, it's a nuisance to get the panicked calls at 10 at night from guest-wannabes thwarted by a closed pass, concerned that we're gonna charge them because they just can't "get there from here" and we have to explain to them in sleep-deprived voices that avalanches are an act of God, and they just need to hole up in a motel on the Interstate and we won't charge them for their reservation.
Don't get me started on the two UK couples who were so disappointed at not getting the chocolate cake that we had promised them (as a joke) because of an avalanche last winter, that they drove the long way (4 hr) around the avalanche (and, damn, told us what they were doing), so that at 9 o'clock at night, I baked a cake timed for their arrival.
They were so tired when they arrived and just wanted to go to bed that I didn't have the heart to deliver my speech: "You better eat that damned cake, or there'll be blood on the floor."
They've already booked with us for next winter; I've promised to bake another cake; and I swear, it the weather goes sour, CNN will be reporting on an ax murder in Grand County..