I’ve seen this go both ways.
The price of a groupon is already low to attract new buyers, and the company issuing the groupon only gets half of the revenue (groupon gets the other half). So, a business that’s thinking about doing this should hopefully do the math and know that if they’re doing a $200 unlimited membership for $50, they still have to be able to pay their instructors, and then estimate the volume of business they can expect from the deal to decide whether it’s actually profitable. So one place where I worked that ran a groupon, my wages were exactly the same.
Different club, different example, different results. A few years ago, there was a “3 for 100” personal training deal. For that particular deal, the trainers were paid $12 an hour, which is lower than standard pay scale. When people purchased that package, trainers had the option of taking those clients or not. The way it was explained to trainers was that if they need the business, this gives them access to new customers that they might be able to retain at regular training rates. If they didn’t need the business, then they didn’t have to do it but would have no access to the business leads generated.