why is my backup so large?

I have asked this before but I have not gotten a resolution. I back up very little. I have 617 contacts. 90% of those are just phone numbers; only a few email addresses and only one persons photo. I also back up the few NOTES I have along with Safari - only so I keep my bookmarks. However, i continue to get messages that my backup size is nearing 5.0G. HOW IS THIS POSSIBLE?!?!. I back up NOTHING. When I look at the icloud storage page (on my phone or on a PC) it shows the purple bar ("backups") is huge (4.4G) and my orange bar ("docs") is almost invisible (11.76mb). What is in the "backup" that is so freaking big? Part of me feels this is just apples way of making us pay more than necessary. I have deleted the backup, deleted a ton of contacts and gotten a fresh backup without any change. Please help me