It may not be theft, but it is stealing :

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Stealing: the action or offence of taking another person's property without permission or legal right and without intending to return it; theft.

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Regardless if there is anything physical missing, you're still obtaining something for which you don't have the ownership rights, therefore another persons property.

And somewhere there's a starving artist that would get $0.25 per purchase that now gets nothing, so you could argue that you're stealing from the artist.