It's not stealing in that sense. You're enshrining "devs can't sell a 1 time payment license to an ongoing service" as a right and I simply disagree.
Your framing relies on devs not being allowed to sell this license. I don't think banning them is healthy.
If they marked the buy button "license" like California will soon mandate, would that suffice for you, or do you actually demand a perpetual experience?
Edit: also corps frequently short each other very slightly all the time. No one makes some outrage about small amounts like that.