This sentence is from TOEFL.
We all tended to take these places for granted, but I do not know what we would have done to entertain ourselves without them.
(for the context, these places refers to a movie theater and an amusement park.)
I understand the overall meaning of the sentence, but I really do not know and want to know why ourselves put in there.
Is there any syntactic structure that ourselves should put in that position?
I think the sentence is makes sense without ourselves. If I omit it, then the sentence will be ungrammatical?