Baby classes - infection risk

Brought my 3 month old to a class recently. Lots of young babies there, youngest probably 6 weeks. I was very surprised when one of the activities was placing all the babies in a small inflatable ship all at the same time. All touching each other as it was so small. I wouldn’t consider myself germaphobic by any means but I found encouraging such close contact between tiny unvaccinated babies a little reckless. The instructor did say “if you feel comfortable” in fairness but I still found it odd. Am I the problem here?