Experience working with outsourcing devs from India

I’m managing a small group of devs from India, I work for a company in US and we have like 8 hours difference so It’s hard to meet each other in working hours. So we meet in our morning which is their afternoon, but I’ve noticed that they tend to stay for a lot longer like it’s 8 or even 10 pm and they are still working. So I keep telling that if they are stuck it’s ok they can come back and try to solve tomorrow, that they should rest or enjoy their afternoons.

I’ve noticed this too with other devs I’ve worked with in the past from India, is it normal? Has anyone had to deal with this before?