Cost of pissing off inactive user: Essentially zero.
Cost of convincing inactive user to come back: Positive.
Add in a bunch of other factors like some product manager twisting stats to make it look like they are getting users back even if they really aren't and you see why it happens.
Cost of sending spam: Effectively zero.
Cost of pissing off inactive user: Essentially zero.
Cost of convincing inactive user to come back: Positive.
Add in a bunch of other factors like some product manager twisting stats to make it look like they are getting users back even if they really aren't and you see why it happens.