subscriber vs customer

subscriber and customer both are nouns.

Word	Noun	Adjective	Verb	Adverb
subscriber	Yes	No	No	No
customer	Yes	No	No	No

As nouns, customer is a hypernym of subscriber; that is, customer is a word with a broader meaning than subscriber:

subscriber: someone who contracts to receive and pay for a service or a certain number of issues of a publication
customer: someone who pays for goods or services

Other hypernyms of subscriber include client.

subscriber (noun)	customer (noun)
someone who contributes (or promises to contribute) a sum of money	someone who pays for goods or services
someone who contracts to receive and pay for a service or a certain number of issues of a publication
someone who expresses strong approval