1. Because at its core, this is about personal property rights that we already (used to) have. When we "bought" something, we owned it and it couldn't legally be taken away from us. With digital media these rights have been eroded and laws have been slow to catch up. We're just asking for existing consumer protection laws and personal property rights to be adapted and/or enforced for digital products.

2. The idea of a free market relies on consumers having perfect information about the product at the time of purchase. If one product page said "Buy", and the other one said "Rent for 3 months or more, at our discretion", then consumers could make an informed decision.

Right now both product pages are allowed to say "Buy", and so the predatory business practices are financially rewarded rather than being treated as fraud.

The only time a digital product (or any other internet-dependent product) should be allowed to use the word "Buy" is when all of its features would remain functional even if the company behind it and all of their servers ceased to exist. For multiplayer games that would mean having the option to self-host a server. For other media that would mean a downloadable, DRM-free copy.

3. Since this practice is profitable, we can expect it to be adopted by an ever-growing number of companies. That's capitalism and we need laws to protect consumers from predatory business practices.

4. At the time of purchase, you don't know whether you're going to get screwed later down the line, so eventually, the only real choices are going to be to avoid the entire sector, or piracy. That's a problem for both sides.