I think what people actually uses them for is very different than what tech and marketing think its for, but there is a massive market and everyday people love it to play music, call another room in a big house, control the light, check what's on tv tonight and if it's raining tomorrow.
Having my 64 years old mom emptying her fridge and then randomly saying "Alexa, what can I cook with VEGETABLE ? [answer] Okay, remind me tomorrow morning" was something very opening, as was "alexa, where is my PRODUCT" to hear about when its delivered.
Especially since I - a tech user - was a first buyer of many of these techs but mostly don't use them.
My mom doesn't know how to use tech. She makes a face when the TV remote has button that are not numbers and arrows, she still doesn't understand nor care about what the 3 buttons at the bottom of her android phone do (home / back / ...), but she has fully integrated alexa into parts her daily routine, yet completly left it out of others that it could handle.
The last time I saw something that eye opening about tech for non tech user was chromecast/firetv.
So yes, I totally understand why those companies want that spot, because whoever gets my mom queries gets her ad profile, gets her delivery orders, her music subscription, dictates what compatible brands she will use, etc ...