Google pays their oncall a % of their full-time base salary depending on the oncall tier (5 min response time vs 30 minutes).
This should probably be required - there is a different mindset and set of restrictions when you're expected to pick up a page. It also forces companies to use on-call judiciously - not every service needs a 5 min SLO.
When I quit Amazon and went to work at Google I had my mind blown by actually getting compensated to be on-call outside work hours. My coworkers shook their heads and told me I wasn't the first.
When I worked there I spent a lot of time talking teams out of a 5min commitment. It’s really crazy.