Sounds like Adobe hired some executives from the cable TV or satellite TV industry, where the fine print on some packages locks you into 24 or 36 month contract terms. They know
exactly how to do it with the minimum legal amount of notice to the customer when signing up, and how to write the terms of service for acceptance to make it ironclad. Same with 2-3 year terms on cellular carriers with a "free $0!" new samsung phone.
For a long time the local telephone company in British Columbia (Telus) was giving away "free" xboxes or 46 inch flat screen TVs if you locked yourself into a triple play service contract. Of course the buy-out price to end the contract early far exceeded the value of the product given out.