You are comparing apples to potatoes. Every city has cleaning and janitorial service companies (I worked for one in high school). Obviously
that model works. We pay our housekeeper $60/week and she's amazing.
What doesn't work is selling a service–cleaning or otherwise–for $20 when you have to pay the contractor $50 and a CAC of $12 (spitballing BTW).
At least Groupon shared the deal price with the restaurant and had some built-in virality.
At least Uber doesn't have to deal with drivers trying to end-around the marketplace and go directly at customers.