they pretty much claim ownership for anything and everything you submit to them. they need it in some useable format, which "encrypted" is not. what they use their data for is not our concern, since we no longer own it
from their ToS:
"Any data, text, graphics, photographs and their selection and arrangement, and any other materials uploaded to the Service by you is “Your Content.”"
"By uploading, distributing, transmitting or otherwise using Your Content with the Service, you grant to us a perpetual, nonexclusive, transferable, royalty-free, sublicensable, and worldwide license to use, host, reproduce, modify, adapt, publish, translate, create derivative works from, distribute, perform, and display Your Content in connection with operating and providing the Service"
from their ToS:
"Any data, text, graphics, photographs and their selection and arrangement, and any other materials uploaded to the Service by you is “Your Content.”"
"By uploading, distributing, transmitting or otherwise using Your Content with the Service, you grant to us a perpetual, nonexclusive, transferable, royalty-free, sublicensable, and worldwide license to use, host, reproduce, modify, adapt, publish, translate, create derivative works from, distribute, perform, and display Your Content in connection with operating and providing the Service"