I have enough Echoes to cover my whole place within speaking distance and they serve as fancy voice-activated light switches and also timers, radios/music/podcast players (via Spotify) and calculators/measurement converters. They also provide local weather alerts and let me know when an Amazon package has arrived, both of which are nice.

But whenever it tries to sell me anything, I get annoyed

Thanks for mentioning the Amazon package alert. I hadn’t set mine up.