Although you may have learned that こと means "thing" or is used for making gerunds such as 歩くこと(working), the original concept of the word is so much complicated, according to a Japanese dictionary. I think the answer your are looking for is that こと implies that the object has something abstract as well as concrete inside FOR YOU, like human beings, academic subjects, pets, countries, hobbies, etc. For example, if you say "私はアップル製品が好きです", of course it means "I love Apple's products" or "I like Apple's products". The important thing here is that the sentence implies kind of preference for an industrial product, it's a very tiny nuance, though. On the other hand, if you say "私はアップル製品のことが好きです",...

～のことが好きです is an indirect expression of ～が好きです. We use it when we confess our love to someone at the first time with some hesitation.