ExploderWizard
Hero
As a GM I don't agree with this.
For example, it is very common in fantasy RPGing for the players to set out an order of watch whenever their PCs camp in the wilderness or the dungeon. This is a convention arising (I imagine) out of old-style wandering monster play. It also has a certain degree of realism about it - there is something sensible about maintaing a watch while camping in dangerous territory.
But by no means is it important. It's almost always trivial and irrelevant, at least in my games where I use overnight attacks only quite rarely.
There are a lot of other things that players have their PCs do (searching rooms and corpses, haggling over prices etc) because these are simply conventions of fantasy RPGing, or genre conventions. But a lot of them aren't important at all, and are (in my experience) precisely the sorts of things that can suck up time needlessly if the GM doesn't keep a tight rein on them.
it is good to have some perspective on these things. As the DM, players keeping watch isn't an important activity. Because you know the liklihood of an attack happening it doesn't seem important. The players don't know that. If nothing happens, then the night passes without incident, not much time spent, and the action moves on.
If players are interested in talking to NPC's thenI try and make it worth their while sometimes by having a seemingly random NPC that is very much worth talking to. These kinds of activities are indications that the players are interested in interacting with the campaign world beyond the strictly mechanical level and that they view NPC's as something other than background scenery. All qualities that a DM is considered fortunate to have in a group of players. I wouldn't dream of taking steps to halt this sort of interest in the campaign.