Do I really need a subscription to use a smart pet camera?

No. Several models in this roundup (eufy E30, TP-Link Tapo C200, Kasa EC70) store video locally to an SD card and work fully without a paid plan. Furbo's newer Mini and 360° variants increasingly gate features like barking alerts and cloud history behind the Furbo Nanny subscription, which specialist subreddits repeatedly flag as a frustration. If you want treat-tossing specifically, you are likely paying a subscription; for everything else, you can avoid one.