Sounds like they hired out to a 3rd party for customer surveys, and one of the ways that company makes money is "bundling" questions.
The sender was identified as "Groupe Nordik — CROP."
Groupe Nordik is Thermea's parent company. CROP, or the Centre for Research on Public Opinion, is a third-party research firm.
So, they offer to take a list of clients, reach out for customer survey, and interpr/relay the results to the company.
But to make extra money, they throw additional questions on the end, then sell those to a different client.
Because the highest priced polling data would be something that agrees with the far right, that's what they're fishing for.
A normal person would just quit the survey, so the bulk of the responses generated will say that these views are overly supported.
The spa is just a victim.