Document Bookmarks (created while creating the QVW) adds to the size of the QVW. So more bookmarks you have during creation of the QVW will increase the size of the QVW. You can test this by observing the size of the QVW while adding a bookmark and saving the document. So unless required you should not create document bookmarks.
Bookmarks created by the end users while interacting the document at the Access Point will be added to the .SHARED binary file under the User Document folder. also known as one of the Server Objects as they are created with the help of a server.
Now in your case the Bookmark size is really big. I would suggest you to make some observation on your QVW.
For example. Create a bookmark and observe the size before and after. Binary load the QVW into another and do not create any UI Objects in the second one and then create bookmark and observe the size. I hope you will find some conclusions.
Given below is my observation on few sample documents which I created in my local system.
QVW Original Size ------- After Creating Bookmark ----- # of records
17,859 KB ------- 17,864KB ------ 153,044
4,680 KB ------- 4,689KB ------ 14,978
17,269 KB ------- 17,276 KB ------- 533,000
The last qvw is without any UI objects just a binary load of another QVW so its all data in the last qvw.