Agreed! The fact that we had a Wix site, and it was incredibly easy to upload site, and then switched to Shopify and have trouble, is quite frankly ridiculous.
I just spoke to Shopify support and they claim this is the way it works if you have product variants. They only send over 1 image for those types of products. What a horrible service, how can they not get the synchronization properly working for such a major platform??