For me it is the evening activities. Some of these 2 and 3 year olds are run ragged being dragged from gymnastics, to swimming, to kindermusik to playgroup to ...... Then they come to daycare exhausted and I suggest a game or activity and all these imploring eyes look at me and I feel so bad for them. They have no down time at all - lest they get bored.
When they do play it is mechanical and shows very little imagination. Makes for long days for me sometimes.