Thai approach to sparring

I’m currently a year into Muay Thai and I’ve been immersing myself into the culture and history of the sport in the context of it within Thailand. Something curious that comes up a lot is that Thai gyms tend to encourage light sparring between athletes. However, as far as gyms go in the area I’m in here in the US, hard sparring is typically encouraged before fights. What’s with the Thai approach to sparring light always, what’s the benefits?