Satchmo thumbnails is great but annoying if we doesn't want to use it.
We can remove all the satchmo_thumbnails calls from templates, but as it's machinery is called when viewing product admin area, it will generate thumbs.
There is a lot of case where we don't want the system to automatically generate thumbs, for example in case of migration from other cart system, or if you work with webservices that directly send images via ftp.
Ok i can extend satchmo admin templates and redefined some models, but i think it's better to have the ability to connect what we need than extends some to make disappear what you doesn't need and it's more easy to put a logic on to manage thumbnail and others images relatives stuff than to hack existing picture = ImageWithThumbnailField.
So i've made a little patch that give us a new config value for settings if make_admin_thumbnails function from thumbnails.utils will make or not thumbs...
It's done with livesettings options, but i don't really know if it's pertinent to let this options within admin back office cause i can't find a case where a manager needs to change media path or other images relatives configuration options...
Let me know if it's ok for you