Most of the likes come from the hashtags and not from followers thats true.
You can say what you want to back your words. For instance,
@08.04.1994,
@oldaccount322 liked your picture. These looks like a spam account solely for spam purposes(liking, following, etc). Quite a lot of your followers are still using the default profile picture too.
Those kind of followers you can get free using many apps fron apple or google store, based on points gained for followings or likes you give.
So most of the accounts were created for spam, since you dont want have 5000 random followings just to make some points faster.