Yoru - no worries, we are glad to have you pop on and say hello when you are up to it - sometimes I just like downtime at home, not going anywhere or having to be responsible for anything or time just chillin with family or vegging watching a show, reading a book...
Alicat - we love having you but you do need to get the homework done... we don't want to be considered a bad influence after all
In a social situation I always try to be polite and curtious and try to come up with something to ask but it can be awkward. I guess it depends to if there is a purpose to the event or meeting or occasion.