Grasshoppers

The concept of "sleep", as far as I understand it, is not applicable to insects, since sleep is not just a general decrease in the activity of the body, but something more complex (otherwise there would be no dreams), and all this is in some connection between the cortex and subcortex, since the central nervous system in insects is arranged somewhat differently, and other concepts are needed here. In general, whether they can be active around the clock or not - I don't know, maybe yes. That is, they do not "sleep"at all. And why exactly about grasshoppers question-they actually are different...

I think the activity of their rudiments can decrease at any time, but "sleep" for them is impossible even because they can not close their eyes, which means the frequency of the brain must be very much reduced so that the brain can not voprinimat constantly coming images.
Let's conclude that they sleep when they are drunk and no one and nothing bothers them

So snakes can't close their eyes, but they probably still sleep - not necessarily, because you can "look, but not see", you wrote it yourself.

I mean, concentration is more difficult, although they don't care - they don't have consciousness, which means they don't bother so stupidly
Another example is that during hypnosis, a person's brain activity decreases very much, but still he does not sleep (1 site still remains active). Perhaps insects have something similar. Or perhaps they also have a dream, only it is expressed in a different way.