Can you be a consumer and not a customer?

Yes, you can be a consumer and not a customer. A consumer is someone who uses or consumes a good; it doesn't matter whether or not you're the one who purchased it. Children and pets are the most common type of consumers, as they'll consume food or toys that someone else bought for them.

You can also be a consumer and not a customer if you receive an item as a gift. You're not the one who bought it, but you will be the one to use it. In addition, if you buy an item with the intention to resell it without using it, then you're a customer but not the consumer.